Improving the Final Atmospheric Seal of Conserved Archaeological Iron from Marine Sites: A Case Study of Cannon Conservation in Louisiana

Improving the Final Atmospheric Seal of Conserved Archaeological Iron from Marine Sites: A Case Study of Cannon Conservation in Louisiana | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Improving the Final Atmospheric Seal of Conserved Archaeological Iron from Marine Sites: A Case Study of Cannon Conservation in Louisiana Christopher Dostal This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5404669/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 30 Jun, 2025 Read the published version in Journal of Maritime Archaeology → Version 1 posted 7 You are reading this latest preprint version Abstract The conservation of iron artifacts from marine archaeological sites faces persistent challenges due to post-recovery electrochemical corrosion. This study investigates the efficacy of a novel conservation treatment that combines microcrystalline wax with a paint overlay, aiming to improve the final atmospheric seal of conserved iron artifacts. The research was conducted at the Conservation Research Laboratory (CRL) at Texas A&M University, involving the treatment of two historically significant cannons with this dual-layer method. The cannons were exposed to controlled yet rigorous environmental conditions to test the durability and protective quality of the treatment. The findings indicate that the combined use of microcrystalline wax and paint significantly enhances corrosion resistance while maintaining the aesthetic and structural integrity of the artifacts under various climatic exposures. This paper discusses the experimental procedures, the resulting data, and the practical implications of this treatment, advocating for its application in both museum settings and outdoor displays. The study contributes a substantial advancement to conservation practices by offering a reversible and effective solution that upholds the historical value of the artifacts while extending their lifespan. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction The preservation of iron artifacts recovered from marine archaeological sites presents significant challenges, particularly in combating the ongoing issue of electrochemical corrosion. Iron, which is the constituent component of many maritime archaeological contexts, especially historical-period ships, is notably vulnerable to corrosion once it is exposed to the dynamic post-depositional environments of marine sites. This vulnerability is well-documented in the literature, where it is recognized as a critical issue that threatens the long-term preservation of these cultural heritage artifacts (North and MacLeod 1987 ; Moore 2015 ; Grousset et al. 2016 ; Remazeilles et al. 2021; Shifler 2022 ). Traditional conservation methods, including electrolytic reduction and chemical stabilization, have demonstrated considerable success in mitigating the immediate risks associated with corrosion (North 1987 ; Hamilton 1998 ). Additionally, consistent innovation over the last 50 years has produced a trove of experimental new conservation methods, including silane self-assembled monolayers, bacterial coatings, plasma-based reduction, and more (Ashkenzi et al. 2017; Comensoli et al. 2017 ; Elsayed 2019 ). These techniques restore iron artifacts to a more stable condition by removing corrosive elements and stabilizing the metal's surface. However, the long-term preservation of these artifacts under atmospheric conditions continues to be problematic. The final step in the conservation process, which involves applying a sealant to protect the artifact from ongoing atmospheric corrosion, has not been as extensively studied as the initial stabilization methods. Previous research has primarily focused on the application of waxes, resins, or paints as final protective layers. The sealant chosen tends to be based on curation environment, pre-conservation condition, and personal preferences (Keene 1984 ; Einarsdottir 2012; Harpers Ferry Center 2024). While wax coatings are favored for their effectiveness in driving moisture out while also creating a moisture barrier, they are often considered unsuitable for outdoor displays due to their susceptibility to environmental conditions. Conversely, paint provides a more durable barrier against physical wear and environmental exposure, but it generally does not drive moisture out of the metal during its application. The consensus in the field has generally favored the use of wax coatings for indoor displays and paint for outdoor settings, although the reversibility of these treatments remains a topic of debate among conservation professionals (Logan and Selwyn 2007 ). It has also been long-held anecdotally that paint would not sufficiently adhere to wax, hence the reason they were not combined in the past. This study seeks to address the existing gap in the literature by evaluating the efficacy of a dual-layer conservation treatment that combines microcrystalline wax with a paint overlay. The primary objective of this research is to develop a more robust atmospheric seal that offers enhanced corrosion resistance while preserving the aesthetic and historical integrity of the artifacts. The study focuses on the conservation of two historically significant cannons, which were subjected to a combination of wax and paint treatments, and subsequently exposed to varying environmental conditions to assess the durability of the protective layers. The study is particularly relevant in the context of outdoor displays and artifacts that are accessible to the public, where the preservation of both the material and visual aspects of the artifact is crucial. By examining the combined effects of wax and paint, this research aims to provide a comprehensive understanding of how these materials interact and how they can be optimized to extend the lifespan of iron artifacts in challenging environmental settings. Methods Artifact Selection and Initial Preparation In June 2021, the Conservation Research Laboratory (CRL) at Texas A&M University was contracted by the Louisiana Department of Culture, Recreation, and Tourism to conserve two iron cannons recovered from New Orleans, an 18-pounder carronade and a Blomefield-pattern 9-pounder. The Blomefield pattern 9-pounder (Fig. 1 ) was selected for this study because of a mid-process decision to change the curation plan. Upon arrival at the CRL, both cannons underwent extensive mechanical cleaning to remove surface encrustations and corrosion products. This was followed by an electrolytic reduction process, which is a well-established method for stabilizing iron artifacts. The electrolytic reduction process involved three stages of current density: 0.001 to 0.005 amp/cm² to reduce ferrous corrosion compounds to a more stable state, 0.05 amp/cm² for chloride removal, and 0.1 amp/cm² for mechanical cleaning via hydrogen evolution. Electrolytic treatment continued until chloride concentration remained below 10 ppm as analyzed via mercuric nitrate (Hg(NO3)2) titration (Hamilton 1998 ). After the electrolytic treatment, the artifacts were subjected to a series of boiling deionized water baths to eliminate any residual electrolyte. At this stage, historical cast or wrought iron is composed of a composite mix of graphite, metallic iron, and reduced iron corrosion in the form of magnetite. With the hot water from the rinse promoting electron exchange from the anodic graphite to the cathodic metallic iron, the surface of the object will begin corroding again immediately upon removal from the water, necessitating the application of a corrosion inhibitor (North and MacLeod 1987 ; Kusmierek and Chzescijanska 2015). Application of Tannic Acid Following the electrolytic reduction, the cannons were treated with three coats of 20% technical grade tannic acid dissolved in deionized water and ethanol. The application of tannic acid is a critical step in the conservation process as it forms a protective ferric tannate layer (Fe 2 (C 14 H 7 O 9 )(OH) 3 ) on the surface of the iron, serving as a corrosion inhibitor (Pelikan 1966 ). The method of application varies according to the size and accessibility of the artifact's surfaces. For these two cannons, paint brushes were used along with modified tools such as tennis balls or rags attached to bamboo poles were used to ensure thorough coverage of the interior surfaces (Fig. 2 ). Microcrystalline Wax Treatment Once the tannic acid application was completed, the cannons were submerged in molten microcrystalline wax, which was maintained at a temperature of 175°C (Fig. 3 ). The submersion process allowed the wax to penetrate the micro-voids within the iron, effectively displacing any remaining moisture and forming a solid protective barrier upon cooling. The wax was then allowed to cool to approximately 100°C before the artifacts were removed, ensuring the formation of a durable and consistent thickness protective layer. This wax treatment is advantageous not only for its protective properties but also for its reversibility, which is a crucial consideration in conservation ethics, allowing future treatments to be applied without damaging the artifact (Sonneborn 2022 ). Experimental Paint Application In May 2022, the CRL was informed that one of the cannons, specifically the Blomefield 9-pounder, would be displayed outdoors. Instead of stripping the wax and painting, the CRL decided to experiment with applying paint directly over the existing wax layer to provide additional protection against environmental exposure. A rusty cast iron floor drain grate was obtained and conserved using the same methods as the cannons, to act as a test sample for this approach. After it was removed from the wax, the grate was painted with the standard paint used by the CRL 1 and placed on a concrete ledge that was painted black outdoors in Bryan, Texas, for an initial exposure period of one month. During this period, the grate was exposed to average daily temperatures of 27°C, with highs of 36°C (US Department of Commerce, 2022). Observations indicated that the paint adhered well, with no signs of loosening or detachment, prompting the application of the same treatment to the Blomefield cannon. The cannon received an undercoat of cherry-red paint, followed by two coats of black paint, in accordance with recommendations from the National Park Service for outdoor displays. The cherry-red undercoat serves as a visual indicator of wear, making it easier to determine when maintenance is required (Steven Roberts, personal communication April 2018). Benjamin Moore Super Spec™ HP D.T.M Alkyd Low Lustre paint, Black P23 80 Results Performance of the Dual-Layer Treatment The application of the microcrystalline wax and paint overlay demonstrated substantial improvements in corrosion resistance compared to traditional treatments. During the 18-month observation period, both the test grate and the Blomefield-pattern cannon exhibited minimal signs of corrosion, despite being exposed to extreme environmental conditions, including temperatures exceeding 40°C during the summer and multiple freeze-thaw cycles in winter (Figs. 4 , 5 ). Monitoring of the Blomefield cannon indicates that the dual layer treatment has similar corrosion resistance observed in wax-treated cannon that are stored in climate-controlled curatorial spaces. The protective layer formed by the paint adhered consistently to the wax, providing an additional physical barrier against environmental factors such as rain, hail, and wind. No significant detachment or degradation of the paint layer was observed, indicating a successful application that enhanced the long-term durability of the treatment. Comparative Analysis of Surface Protection A comparative analysis was conducted between the dual-layer treatment and traditional wax-only and paint-only treatments. Samples treated with wax alone have excellent corrosion resistance, but as stated above, they much be kept indoors to prevent melting or eroding away the wax. Samples that go through the same ER process but only receive paint, while initially effective, begin to show signs of corrosion at the base layers within 1–2 years of being exposed to the elements. In contrast, the dual-layer treatment effectively addressed these issues, with the microcrystalline wax displacing moisture during the submersion process and the paint providing an additional layer of environmental resistance. This synergy resulted in a significant reduction in the typically expected visible corrosion after 18 months, highlighting the combined treatment’s superiority in both laboratory and real-world settings. Figure 6 shows that the treatment is holding up despite fairly rigorous interactions with the public, as indicated by the glossy wear marks on the paint that is likely the result of people sitting atop the cannon. Discussion The dual-layer treatment combining microcrystalline wax and a paint overlay represents a significant advancement in the conservation of iron artifacts, particularly those displayed outdoors or in public settings. The results of this study demonstrate that this method effectively mitigates the primary limitations of each material when used independently, providing enhanced corrosion resistance and maintaining the artifacts' structural and aesthetic integrity. Synergistic Effects and Enhanced Durability The combined use of microcrystalline wax and paint addresses critical issues faced in iron conservation. The wax displaces residual moisture within the artifact's micro-voids, creating a protective barrier that significantly reduces the electrochemical processes responsible for corrosion. The subsequent application of paint not only protects the wax from environmental wear but also adds an additional layer of physical protection against mechanical damage, UV exposure, and other environmental stressors. The adhesion tests confirmed that the paint adheres well to the wax, contradicting the long-held assumption that paint would not bond effectively to wax-treated surfaces. These findings suggest that the dual-layer method not only prolongs the lifespan of conserved artifacts but also minimizes the frequency and extent of maintenance required, making it a practical choice for outdoor displays. Practical Implications for Conservation Practice The success of the dual-layer treatment has important implications for conservation strategies, especially for artifacts exposed to varying environmental conditions and public interaction. The treatment's effectiveness in reducing corrosion without compromising the artifact’s historical appearance underscores its suitability for both museum settings and outdoor installations. The reversibility of the wax layer also aligns with ethical conservation practices, ensuring that future treatments can be applied without permanent alterations to the artifact. Furthermore, the visual inspection benefits of the cherry-red undercoat—serving as an early indicator of wear—add a practical aspect to the conservation strategy, enabling conservators to monitor and address maintenance needs proactively. This method provides a balanced approach that enhances protection while respecting the artifact's historical and aesthetic significance. Limitations and Future Directions While the results are promising, the long-term performance of this dual-layer treatment requires further evaluation. Future studies should focus on multi-year assessments to validate the durability of this method under different climatic conditions. Additionally, exploring variations in wax and paint formulations could further optimize the treatment’s effectiveness, potentially broadening its applicability to other types of metal artifacts beyond iron. Future research could also involve comparative studies with other emerging conservation techniques, such as advanced sealants, to establish a more comprehensive understanding of the best practices for preserving metallic heritage artifacts (Favre-Quattropani et al. 2000 ; Ashkenazi et al. 2017 ; Blahova et al. 2020). Conclusion This study contributes a novel and practical approach to iron conservation, demonstrating the effectiveness of combining microcrystalline wax with paint to enhance corrosion resistance. The dual-layer treatment provides a durable and aesthetically pleasing solution that addresses the challenges faced by traditional methods, making it particularly well-suited for artifacts in outdoor or high-traffic environments. The integration of this method into broader conservation practices has the potential to significantly improve the preservation of iron artifacts, ensuring their longevity and accessibility for future generations. As the field of conservation continues to evolve, approaches that combine traditional knowledge with innovative techniques, like the dual-layer treatment, will be essential in safeguarding our cultural heritage. Declarations This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Author Contribution It is a single author manuscript Acknowledgement Special thanks to Dr. Chip McGimsey, State Archaeologist, LA division of Archaeology for allowing us to proceed with the experiment. This work was facilitated by the exceptional staff conservators at the CRL who helped with these experiments, especially John Hamilton. Finally, a hearty thank you to Chloe Stephan at the Maritime Museum Louisiana, whose photos were crucial to this paper. References Ashkenazi D, Nusbaum I, Shacham-Diamand Y, Cvikel D, Kahanov Y, Inberg A (2017) A Method of Conserving Ancient Iron Artefacts Retrieved from Shipwrecks Using a Combination of Silane Self-Assembled Monolayers and Wax Coating. Corros Sci 123:88–102. https://doi.org/10.1016/j.corsci.2017.04.007 Blahová L, Horák J, Přikryl R, Pekárek J, Tkacz J, Menčík P, Krčma F (2020) A Novel Technology for the Corrosion Protection of Iron Archaeological Artefacts Using Parylene Base Removable Bilayer. J Cult Herit 42:28–35. https://doi.org/10.1016/j.culher.2019.09.001 Comensoli L, Maillard J, Albini M, Sandoz F, Junier P, Joseph E (2017) Use of Bacteria to Stabilize Archaeological Iron. Appl Environ Microbiol 83(9):e03478–e03416. https://doi.org/10.1128/AEM.03478-16 Einarsdóttir S (2012) Mass-Conservation of Archaeological Iron Artefacts: A Case Study at the National Museum of Iceland. Institutionen för Kulturvård, Göteborgs Universitet Elsayed A (2019) Low-Pressure Plasma Treatments for Cleaning Metallic Heritage Artefacts. Dissertation, Politecnico di Torino Scoula di Dottorato Favre-Quattropani L, Groening P, Ramseyer D, Schlapbach L (2000) The protection of metallic archaeological objects using plasma polymer coatings. Surf Coat Technol 125(1–3):377–382. https://doi.org/10.1016/S0257-8972(99)00579-4 Grousset S, Bayle M, Dauzeres A, Crusset D, Deydier V, Linard Y, Dillmann P, Mercier-Bion F, Neff D (2016) Study of Iron Sulphides in Long-Term Iron Corrosion Processes: Characterisations of Archaeological Artefacts. Corros Sci 112:264–275. https://doi.org/10.1016/j.corsci.2016.07.022 Hamilton D (1998) Methods for Conserving Material from Underwater Sites. Texas A&M University, College Station, TX Harpers Ferry Center, Museum Conservation Services (2024) Resource for Understanding Conservation Coatings for Outdoor Iron Cannons. National Parks Service Keene S (1984) The Performance of Coatings and Consolidants Used for Archaeological Iron. Stud Conserv 29:104–106. https://doi.org/10.1179/sic.1984.29.Supplement-1.104 Kusmierek E, Chrzescijanska E (2015) Tannic acid as corrosion inhibitor for metals and alloys. Mater Corros 66:169–174. https://doi.org/10.1002/maco.201307277 Logan J, Selwyn L (2007) Care and Cleaning of Iron. Canadian Conservation Institute Notes 9/6, Minister of Public Works and Government Services Canada Moore JD (2015) Long-Term Corrosion Processes of Iron and Steel Shipwrecks in the Marine Environment: A Review of Current Knowledge. J Mari Arch 10:191–204. https://doi.org/10.1007/s11457-015-9148-x North NA (1987) Conservation of Metals. In: Pearson C (ed) Conservation of Marine Archaeological Objects. Butterworths, Sydney, pp 207–232 North NA, MacLeod I (1987) Corrosion of Metals. In: Pearson C (ed) Conservation of Marine Archaeological Objects. Butterworths, Sydney, pp 76–80 Pelikan JB (1966) Conservation of Iron with Tannin. Stud Conserv 11(3):109–115. https://doi.org/10.1179/SIC.1966.014 Rémazeilles C, Lévêque F, Conforto E, Refait P (2021) Long-term Alteration Processes of Iron Fasteners Extracted from Archaeological Shipwrecks Aged in Biologically Active Waterlogged Media. Corros Sci 181:109231. https://doi.org/10.1016/j.corsci.2020.109231 Shifler D (2022) Corrosion Control and Preservation of Historic Marine Artifacts. In: LaQue’s Handbook of Marine Corrosion. Wiley https://doi.org/ 10.1002/9781119788867 Sonneborn (2022) Specifications for MULTIWAX® 180-M Microcrystalline Wax. Sonneborn. Https://www.sonneborn.com/api/sitecore/sblubesapi/downloadresource?docID=multiwax180m424a&type=TechData⟨=englishus Accessed 10 April 2024 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 30 Jun, 2025 Read the published version in Journal of Maritime Archaeology → Version 1 posted Editorial decision: Revision requested 14 May, 2025 Reviews received at journal 03 Dec, 2024 Reviewers agreed at journal 19 Nov, 2024 Reviewers invited by journal 19 Nov, 2024 Editor assigned by journal 08 Nov, 2024 Submission checks completed at journal 08 Nov, 2024 First submitted to journal 06 Nov, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5404669","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":381155223,"identity":"52eeebd7-475d-4301-9b74-89a7510cc2bd","order_by":0,"name":"Christopher 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15:56:08","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":347082,"visible":true,"origin":"","legend":"\u003cp\u003eThe application of tannic acid\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/fbab375fd67bc73d9ce40530.jpg"},{"id":71054362,"identity":"a6f494c3-0296-49f6-bf1c-dfc52223d79f","added_by":"auto","created_at":"2024-12-10 16:04:08","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":52327,"visible":true,"origin":"","legend":"\u003cp\u003eA cannon being submerged in molten microcrystalline wax\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/d8e6762f6ba2ba9912c26447.jpg"},{"id":71053684,"identity":"f48cea3d-daad-4866-9f9b-fb14401b59ee","added_by":"auto","created_at":"2024-12-10 15:56:08","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":387259,"visible":true,"origin":"","legend":"\u003cp\u003eThe conserved Blomefield Pattern 9-pounder after 18 months of exposure\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/43fdafc46753c55f48415877.jpg"},{"id":71054361,"identity":"e11416d9-b7db-41d6-a4d4-c78658baf11f","added_by":"auto","created_at":"2024-12-10 16:04:08","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":102391,"visible":true,"origin":"","legend":"\u003cp\u003eThe Drain Grate after 18 months of exposure\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/6f45b744e8c13c2b52338bf3.jpg"},{"id":71053680,"identity":"e6bbabdb-0003-4934-9e07-c03b34ac5abb","added_by":"auto","created_at":"2024-12-10 15:56:08","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":235883,"visible":true,"origin":"","legend":"\u003cp\u003eDetail of the conserved Blomefield Pattern 9-pounder after 18 months of exposure\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/7679770f89be86e1b404f91a.jpg"},{"id":86178953,"identity":"bf92f26c-40bc-486a-b968-9ec1744197e5","added_by":"auto","created_at":"2025-07-07 16:12:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6515854,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5404669/v1/7035cc6a-85af-4dc1-bf0d-65d14fd4b2fa.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Improving the Final Atmospheric Seal of Conserved Archaeological Iron from Marine Sites: A Case Study of Cannon Conservation in Louisiana","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe preservation of iron artifacts recovered from marine archaeological sites presents significant challenges, particularly in combating the ongoing issue of electrochemical corrosion. Iron, which is the constituent component of many maritime archaeological contexts, especially historical-period ships, is notably vulnerable to corrosion once it is exposed to the dynamic post-depositional environments of marine sites. This vulnerability is well-documented in the literature, where it is recognized as a critical issue that threatens the long-term preservation of these cultural heritage artifacts (North and MacLeod \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1987\u003c/span\u003e; Moore \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Grousset et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Remazeilles et al. 2021; Shifler \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTraditional conservation methods, including electrolytic reduction and chemical stabilization, have demonstrated considerable success in mitigating the immediate risks associated with corrosion (North \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1987\u003c/span\u003e; Hamilton \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e1998\u003c/span\u003e). Additionally, consistent innovation over the last 50 years has produced a trove of experimental new conservation methods, including silane self-assembled monolayers, bacterial coatings, plasma-based reduction, and more (Ashkenzi et al. 2017; Comensoli et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Elsayed \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). These techniques restore iron artifacts to a more stable condition by removing corrosive elements and stabilizing the metal's surface. However, the long-term preservation of these artifacts under atmospheric conditions continues to be problematic. The final step in the conservation process, which involves applying a sealant to protect the artifact from ongoing atmospheric corrosion, has not been as extensively studied as the initial stabilization methods.\u003c/p\u003e \u003cp\u003ePrevious research has primarily focused on the application of waxes, resins, or paints as final protective layers. The sealant chosen tends to be based on curation environment, pre-conservation condition, and personal preferences (Keene \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e1984\u003c/span\u003e; Einarsdottir 2012; Harpers Ferry Center 2024). While wax coatings are favored for their effectiveness in driving moisture out while also creating a moisture barrier, they are often considered unsuitable for outdoor displays due to their susceptibility to environmental conditions. Conversely, paint provides a more durable barrier against physical wear and environmental exposure, but it generally does not drive moisture out of the metal during its application. The consensus in the field has generally favored the use of wax coatings for indoor displays and paint for outdoor settings, although the reversibility of these treatments remains a topic of debate among conservation professionals (Logan and Selwyn \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). It has also been long-held anecdotally that paint would not sufficiently adhere to wax, hence the reason they were not combined in the past.\u003c/p\u003e \u003cp\u003eThis study seeks to address the existing gap in the literature by evaluating the efficacy of a dual-layer conservation treatment that combines microcrystalline wax with a paint overlay. The primary objective of this research is to develop a more robust atmospheric seal that offers enhanced corrosion resistance while preserving the aesthetic and historical integrity of the artifacts. The study focuses on the conservation of two historically significant cannons, which were subjected to a combination of wax and paint treatments, and subsequently exposed to varying environmental conditions to assess the durability of the protective layers.\u003c/p\u003e \u003cp\u003eThe study is particularly relevant in the context of outdoor displays and artifacts that are accessible to the public, where the preservation of both the material and visual aspects of the artifact is crucial. By examining the combined effects of wax and paint, this research aims to provide a comprehensive understanding of how these materials interact and how they can be optimized to extend the lifespan of iron artifacts in challenging environmental settings.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eArtifact Selection and Initial Preparation\u003c/h2\u003e \u003cp\u003eIn June 2021, the Conservation Research Laboratory (CRL) at Texas A\u0026amp;M University was contracted by the Louisiana Department of Culture, Recreation, and Tourism to conserve two iron cannons recovered from New Orleans, an 18-pounder carronade and a Blomefield-pattern 9-pounder. The Blomefield pattern 9-pounder (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was selected for this study because of a mid-process decision to change the curation plan.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eUpon arrival at the CRL, both cannons underwent extensive mechanical cleaning to remove surface encrustations and corrosion products. This was followed by an electrolytic reduction process, which is a well-established method for stabilizing iron artifacts. The electrolytic reduction process involved three stages of current density: 0.001 to 0.005 amp/cm\u0026sup2; to reduce ferrous corrosion compounds to a more stable state, 0.05 amp/cm\u0026sup2; for chloride removal, and 0.1 amp/cm\u0026sup2; for mechanical cleaning via hydrogen evolution. Electrolytic treatment continued until chloride concentration remained below 10 ppm as analyzed via mercuric nitrate (Hg(NO3)2) titration (Hamilton \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e1998\u003c/span\u003e). After the electrolytic treatment, the artifacts were subjected to a series of boiling deionized water baths to eliminate any residual electrolyte. At this stage, historical cast or wrought iron is composed of a composite mix of graphite, metallic iron, and reduced iron corrosion in the form of magnetite. With the hot water from the rinse promoting electron exchange from the anodic graphite to the cathodic metallic iron, the surface of the object will begin corroding again immediately upon removal from the water, necessitating the application of a corrosion inhibitor (North and MacLeod \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1987\u003c/span\u003e; Kusmierek and Chzescijanska 2015).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eApplication of Tannic Acid\u003c/h3\u003e\n\u003cp\u003eFollowing the electrolytic reduction, the cannons were treated with three coats of 20% technical grade tannic acid dissolved in deionized water and ethanol. The application of tannic acid is a critical step in the conservation process as it forms a protective ferric tannate layer (Fe\u003csub\u003e2\u003c/sub\u003e(C\u003csub\u003e14\u003c/sub\u003eH\u003csub\u003e7\u003c/sub\u003eO\u003csub\u003e9\u003c/sub\u003e)(OH)\u003csub\u003e3\u003c/sub\u003e) on the surface of the iron, serving as a corrosion inhibitor (Pelikan \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e1966\u003c/span\u003e). The method of application varies according to the size and accessibility of the artifact's surfaces. For these two cannons, paint brushes were used along with modified tools such as tennis balls or rags attached to bamboo poles were used to ensure thorough coverage of the interior surfaces (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eMicrocrystalline Wax Treatment\u003c/h3\u003e\n\u003cp\u003eOnce the tannic acid application was completed, the cannons were submerged in molten microcrystalline wax, which was maintained at a temperature of 175\u0026deg;C (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The submersion process allowed the wax to penetrate the micro-voids within the iron, effectively displacing any remaining moisture and forming a solid protective barrier upon cooling. The wax was then allowed to cool to approximately 100\u0026deg;C before the artifacts were removed, ensuring the formation of a durable and consistent thickness protective layer. This wax treatment is advantageous not only for its protective properties but also for its reversibility, which is a crucial consideration in conservation ethics, allowing future treatments to be applied without damaging the artifact (Sonneborn \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eExperimental Paint Application\u003c/h3\u003e\n\u003cp\u003eIn May 2022, the CRL was informed that one of the cannons, specifically the Blomefield 9-pounder, would be displayed outdoors. Instead of stripping the wax and painting, the CRL decided to experiment with applying paint directly over the existing wax layer to provide additional protection against environmental exposure. A rusty cast iron floor drain grate was obtained and conserved using the same methods as the cannons, to act as a test sample for this approach. After it was removed from the wax, the grate was painted with the standard paint used by the CRL\u003csup\u003e1\u003c/sup\u003e and placed on a concrete ledge that was painted black outdoors in Bryan, Texas, for an initial exposure period of one month.\u003c/p\u003e \u003cp\u003eDuring this period, the grate was exposed to average daily temperatures of 27\u0026deg;C, with highs of 36\u0026deg;C (US Department of Commerce, 2022). Observations indicated that the paint adhered well, with no signs of loosening or detachment, prompting the application of the same treatment to the Blomefield cannon. The cannon received an undercoat of cherry-red paint, followed by two coats of black paint, in accordance with recommendations from the National Park Service for outdoor displays. The cherry-red undercoat serves as a visual indicator of wear, making it easier to determine when maintenance is required (Steven Roberts, personal communication April 2018).\u003c/p\u003e\u003col\u003e\n\u003cli\u003eBenjamin Moore Super Spec\u0026trade; HP D.T.M Alkyd Low Lustre paint, Black P23 80\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003ePerformance of the Dual-Layer Treatment\u003c/h2\u003e \u003cp\u003eThe application of the microcrystalline wax and paint overlay demonstrated substantial improvements in corrosion resistance compared to traditional treatments. During the 18-month observation period, both the test grate and the Blomefield-pattern cannon exhibited minimal signs of corrosion, despite being exposed to extreme environmental conditions, including temperatures exceeding 40\u0026deg;C during the summer and multiple freeze-thaw cycles in winter (Figs.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eMonitoring of the Blomefield cannon indicates that the dual layer treatment has similar corrosion resistance observed in wax-treated cannon that are stored in climate-controlled curatorial spaces. The protective layer formed by the paint adhered consistently to the wax, providing an additional physical barrier against environmental factors such as rain, hail, and wind. No significant detachment or degradation of the paint layer was observed, indicating a successful application that enhanced the long-term durability of the treatment.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eComparative Analysis of Surface Protection\u003c/h3\u003e\n\u003cp\u003eA comparative analysis was conducted between the dual-layer treatment and traditional wax-only and paint-only treatments. Samples treated with wax alone have excellent corrosion resistance, but as stated above, they much be kept indoors to prevent melting or eroding away the wax. Samples that go through the same ER process but only receive paint, while initially effective, begin to show signs of corrosion at the base layers within 1\u0026ndash;2 years of being exposed to the elements.\u003c/p\u003e \u003cp\u003eIn contrast, the dual-layer treatment effectively addressed these issues, with the microcrystalline wax displacing moisture during the submersion process and the paint providing an additional layer of environmental resistance. This synergy resulted in a significant reduction in the typically expected visible corrosion after 18 months, highlighting the combined treatment\u0026rsquo;s superiority in both laboratory and real-world settings. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e shows that the treatment is holding up despite fairly rigorous interactions with the public, as indicated by the glossy wear marks on the paint that is likely the result of people sitting atop the cannon.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe dual-layer treatment combining microcrystalline wax and a paint overlay represents a significant advancement in the conservation of iron artifacts, particularly those displayed outdoors or in public settings. The results of this study demonstrate that this method effectively mitigates the primary limitations of each material when used independently, providing enhanced corrosion resistance and maintaining the artifacts' structural and aesthetic integrity.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eSynergistic Effects and Enhanced Durability\u003c/h2\u003e \u003cp\u003eThe combined use of microcrystalline wax and paint addresses critical issues faced in iron conservation. The wax displaces residual moisture within the artifact's micro-voids, creating a protective barrier that significantly reduces the electrochemical processes responsible for corrosion. The subsequent application of paint not only protects the wax from environmental wear but also adds an additional layer of physical protection against mechanical damage, UV exposure, and other environmental stressors. The adhesion tests confirmed that the paint adheres well to the wax, contradicting the long-held assumption that paint would not bond effectively to wax-treated surfaces.\u003c/p\u003e \u003cp\u003eThese findings suggest that the dual-layer method not only prolongs the lifespan of conserved artifacts but also minimizes the frequency and extent of maintenance required, making it a practical choice for outdoor displays.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003ePractical Implications for Conservation Practice\u003c/h2\u003e \u003cp\u003eThe success of the dual-layer treatment has important implications for conservation strategies, especially for artifacts exposed to varying environmental conditions and public interaction. The treatment's effectiveness in reducing corrosion without compromising the artifact\u0026rsquo;s historical appearance underscores its suitability for both museum settings and outdoor installations. The reversibility of the wax layer also aligns with ethical conservation practices, ensuring that future treatments can be applied without permanent alterations to the artifact.\u003c/p\u003e \u003cp\u003eFurthermore, the visual inspection benefits of the cherry-red undercoat\u0026mdash;serving as an early indicator of wear\u0026mdash;add a practical aspect to the conservation strategy, enabling conservators to monitor and address maintenance needs proactively. This method provides a balanced approach that enhances protection while respecting the artifact's historical and aesthetic significance.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eLimitations and Future Directions\u003c/h2\u003e \u003cp\u003eWhile the results are promising, the long-term performance of this dual-layer treatment requires further evaluation. Future studies should focus on multi-year assessments to validate the durability of this method under different climatic conditions. Additionally, exploring variations in wax and paint formulations could further optimize the treatment\u0026rsquo;s effectiveness, potentially broadening its applicability to other types of metal artifacts beyond iron.\u003c/p\u003e \u003cp\u003eFuture research could also involve comparative studies with other emerging conservation techniques, such as advanced sealants, to establish a more comprehensive understanding of the best practices for preserving metallic heritage artifacts (Favre-Quattropani et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2000\u003c/span\u003e; Ashkenazi et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Blahova et al. 2020).\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study contributes a novel and practical approach to iron conservation, demonstrating the effectiveness of combining microcrystalline wax with paint to enhance corrosion resistance. The dual-layer treatment provides a durable and aesthetically pleasing solution that addresses the challenges faced by traditional methods, making it particularly well-suited for artifacts in outdoor or high-traffic environments.\u003c/p\u003e \u003cp\u003eThe integration of this method into broader conservation practices has the potential to significantly improve the preservation of iron artifacts, ensuring their longevity and accessibility for future generations. As the field of conservation continues to evolve, approaches that combine traditional knowledge with innovative techniques, like the dual-layer treatment, will be essential in safeguarding our cultural heritage.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eIt is a single author manuscript\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eSpecial thanks to Dr. Chip McGimsey, State Archaeologist, LA division of Archaeology for allowing us to proceed with the experiment. This work was facilitated by the exceptional staff conservators at the CRL who helped with these experiments, especially John Hamilton. Finally, a hearty thank you to Chloe Stephan at the Maritime Museum Louisiana, whose photos were crucial to this paper.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAshkenazi D, Nusbaum I, Shacham-Diamand Y, Cvikel D, Kahanov Y, Inberg A (2017) A Method of Conserving Ancient Iron Artefacts Retrieved from Shipwrecks Using a Combination of Silane Self-Assembled Monolayers and Wax Coating. 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Canadian Conservation Institute Notes 9/6, Minister of Public Works and Government Services Canada\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoore JD (2015) Long-Term Corrosion Processes of Iron and Steel Shipwrecks in the Marine Environment: A Review of Current Knowledge. J Mari Arch 10:191\u0026ndash;204. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s11457-015-9148-x\u003c/span\u003e\u003cspan address=\"10.1007/s11457-015-9148-x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNorth NA (1987) Conservation of Metals. In: Pearson C (ed) Conservation of Marine Archaeological Objects. Butterworths, Sydney, pp 207\u0026ndash;232\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNorth NA, MacLeod I (1987) Corrosion of Metals. In: Pearson C (ed) Conservation of Marine Archaeological Objects. Butterworths, Sydney, pp 76\u0026ndash;80\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePelikan JB (1966) Conservation of Iron with Tannin. Stud Conserv 11(3):109\u0026ndash;115. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1179/SIC.1966.014\u003c/span\u003e\u003cspan address=\"10.1179/SIC.1966.014\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eR\u0026eacute;mazeilles C, L\u0026eacute;v\u0026ecirc;que F, Conforto E, Refait P (2021) Long-term Alteration Processes of Iron Fasteners Extracted from Archaeological Shipwrecks Aged in Biologically Active Waterlogged Media. Corros Sci 181:109231. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.corsci.2020.109231\u003c/span\u003e\u003cspan address=\"10.1016/j.corsci.2020.109231\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShifler D (2022) Corrosion Control and Preservation of Historic Marine Artifacts. In: LaQue\u0026rsquo;s Handbook of Marine Corrosion. Wiley https://doi.org/\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1002/9781119788867\u003c/span\u003e\u003cspan address=\"10.1002/9781119788867\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSonneborn (2022) Specifications for MULTIWAX\u0026reg; 180-M Microcrystalline Wax. Sonneborn. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003eHttps://www.sonneborn.com/api/sitecore/sblubesapi/downloadresource?docID=multiwax180m424a\u0026amp;type=TechData⟨=englishus\u003c/span\u003e\u003cspan address=\"http://Https://www.sonneborn.com/api/sitecore/sblubesapi/downloadresource?docID=multiwax180m424a\u0026amp;type=TechData⟨=englishus\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e Accessed 10 April 2024\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-maritime-archaeology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jmar","sideBox":"Learn more about [Journal of Maritime Archaeology](http://link.springer.com/journal/11457)","snPcode":"11457","submissionUrl":"https://submission.nature.com/new-submission/11457/3","title":"Journal of Maritime Archaeology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-5404669/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5404669/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe conservation of iron artifacts from marine archaeological sites faces persistent challenges due to post-recovery electrochemical corrosion. This study investigates the efficacy of a novel conservation treatment that combines microcrystalline wax with a paint overlay, aiming to improve the final atmospheric seal of conserved iron artifacts. The research was conducted at the Conservation Research Laboratory (CRL) at Texas A\u0026amp;M University, involving the treatment of two historically significant cannons with this dual-layer method. The cannons were exposed to controlled yet rigorous environmental conditions to test the durability and protective quality of the treatment. The findings indicate that the combined use of microcrystalline wax and paint significantly enhances corrosion resistance while maintaining the aesthetic and structural integrity of the artifacts under various climatic exposures. This paper discusses the experimental procedures, the resulting data, and the practical implications of this treatment, advocating for its application in both museum settings and outdoor displays. The study contributes a substantial advancement to conservation practices by offering a reversible and effective solution that upholds the historical value of the artifacts while extending their lifespan.\u003c/p\u003e","manuscriptTitle":"Improving the Final Atmospheric Seal of Conserved Archaeological Iron from Marine Sites: A Case Study of Cannon Conservation in Louisiana","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-10 15:56:03","doi":"10.21203/rs.3.rs-5404669/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-14T15:24:07+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-12-03T21:36:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"254759074954548943958183900717959871153","date":"2024-11-19T20:49:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-19T20:44:43+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-08T08:45:12+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-11-08T08:45:06+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Maritime Archaeology","date":"2024-11-06T17:13:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-maritime-archaeology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jmar","sideBox":"Learn more about [Journal of Maritime Archaeology](http://link.springer.com/journal/11457)","snPcode":"11457","submissionUrl":"https://submission.nature.com/new-submission/11457/3","title":"Journal of Maritime Archaeology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"7309c30a-51f6-4f17-8e63-5b4d50d445e8","owner":[],"postedDate":"December 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-07-07T16:01:14+00:00","versionOfRecord":{"articleIdentity":"rs-5404669","link":"https://doi.org/10.1007/s11457-025-09451-9","journal":{"identity":"journal-of-maritime-archaeology","isVorOnly":false,"title":"Journal of Maritime Archaeology"},"publishedOn":"2025-06-30 15:57:00","publishedOnDateReadable":"June 30th, 2025"},"versionCreatedAt":"2024-12-10 15:56:03","video":"","vorDoi":"10.1007/s11457-025-09451-9","vorDoiUrl":"https://doi.org/10.1007/s11457-025-09451-9","workflowStages":[]},"version":"v1","identity":"rs-5404669","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5404669","identity":"rs-5404669","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}