Stern Encrustation

The Mardi Gras Shipwreck site contained a large stern encrustation, which was recovered the from the site and transported to the Conservation Research Laboratory at Texas A&M University. The encrustation is currently undergoing detailed recording, excavation, and conservation. A final analysis of the artifacts associated with the encrustation is not yet complete, but some artifacts, such as a brush, lead sounding weight and wicker basket, have been identified within the concretion.

Recovery of the Stern Encrustation
Due to the depth of the site, at over 4000 feet, the Mardi Gras shipwreck was investigated and many artifacts were retrieved with a Remote Operated Vehicle, or ROV. In addition to the ROV, Large Artifact Retrieval Tools, or LARTs, were used to raise large artfacts from the ocean floor.

The stern encrustation was recovered from the extreme southeastern end of the site. At left, the encrustation is seen in situ with other adjacent artifacts.

The ROV which was used to investigate the shipwreck site, a Perry Triton XLS-17 provided by Veolia Environmental, is seen at right. The primary tools for artifact recovery were suction pickers, commonly called "sticky feet." Also visible in the picture is a bag of styrofoam cups, which were crushed by the water pressure at the deep site.

Large Artifact Retrieval Tools, or LARTs were used to recover the stern encrustation and to backfill the site. The LARTs were specially designed for use at the Mardi Gras site by Perry Slingsby Engineering in Houston, Texas and were manufactured under the direction of Veolia Environmental Marine Services.

Transport to the Laboratory
The stern encrustation was transported to the Conservation Research Laboratory at Texas A&M University inside a LART. Once removed from the LART, the encrustation was placed in a specially constructed vat where it will undergo conservation treatment.

Above, the stern encrustation is seen within the LART that was used to transport the encrustation to the Conservation Research Laboratory at Texas A&M University.	A crane was used to place the large encrustation on the premises of the laboratory, where it could be moved into a specially constructed vat for desalination and conservation.
Here, the open LART reveals its "clamshell" construction, and a forklift is maneuvered into place behind the encrustation. To prevent the encrustation from drying out, it has been wrapped in wet towels and plastic bags.	On its way to the desalination vat, the encrustation is exposed only briefly. Lead shot are visible in the middle of this image, and the large dome-like feature at the top of the encrustation can be seen. This was thought to be a kettle, but further work has revealed that it is a wicker basket which has been preserved by the various iron artifacts it contained.

Conservation Treatment
Conservation of the stern encrustation begins with deslination. A series of static water baths will lower the salt levels within the encrustation and allow conservators to work with the various artifacts contained within the encrustation. In addition to the concretion, mud which was removed from the ocean floor was sifted for smaller artifacts as well.

The size of the encrustation can be seen here, as well as two different caliber shot. Both lead and iron round shot have been identified within the encrustation, as well as bar shot.	When the encrustation was retrieved from the ocean floor, mud was also brought up from the bottom inside the LART. As this mud may have contained valuable artifacts, it was sifted and examined as well.
The mud is sifted with the aid of a spray of water, and artifacts are retrieved from a mesh screen. .	The stern encrustation is seen from above here, as it is prepared to be lowered into the vat where it will undergo desalination and further treatment.
Once inside the vat, the encrustation is covered with tap water to begin the desalination process.

Texas A&M University | College of Liberal Arts | Location

Citation Information:
Donny L. Hamilton
2007, Mardi Gras Shipwreck Project-On-going work, URL, http://nautarch.tamu.edu/mardigras, Center for Maritime Archaeology and Conservation, Texas A&M University.

This page is maintained by the staff of the Center for Maritime Archaeology and Conservation, Conservation Research Laboratory, Texas A&M University (crl@tamu.edu). The contents of this site - text, images, and data - are intended for personal information only. Downloading of information or graphic images contained herein for private use is not discouraged; however, written permission from the Center for Maritime Archaeology and Conservation is required for the publication of any material. Any use of this information should credit the Center for Marimtime Archaeology and Conservation. For additional details, contact Kevin Crisman ( kcrisman@tamu.edu ) or Donny L. Hamilton (dlhamilton@tamu.edu). Last updated: Monday, 10-Oct-2011 18:19:47 CDT

Stern Encrustation

Recovery of the Stern Encrustation

Transport to the Laboratory

Conservation Treatment