From: Neven Peko <[email protected]> To: [email protected] Subject: [Consdistlist] conservation of mammoth bone and tusk Message-ID: <[email protected]> Content-Type: text/plain; charset=us-ascii
"a few months ago a local diver brought a piece of mammoth tusk (60x30x30 cm) to our Museum which he took out of nearby river. We have kept it in water ever since, and now the time has come to conserve it because it will be featured in an exhibition. do you have any idea how to consolidate it without using solvents such as ethanol or acetone? We would prefer to use a water-based system because of health risks. Also, a large part of our mammoth bones collection was treated in sixties by immersion in diluted PVA or PVAc glue (white thick wood glue). The glue is now flaking of the object, taking with it small particles of bone. Do you have any idea how to chemically remove it without affecting the very porous bone? Also, do you have any suggestions on how to consolidate bone previously treated in this manner?" I've had good results using Acrysol WS-24 for consolidating wet and damp bone and wood artifacts. It's available from the following supplier in the US: http://www.museumservicescorporation.com/scat/co.html I'd recommend starting with a a 10% v/v solution of the consolidant with immersion, then gradually working up to 100% over the course of several weeks in order to achieve as a full a penetration of the as possible. Allow the piece to dry slowly and evenly. If you have a small piece that has become detached from the main artifact, you could experiment with vacuum consolidation, if you have that equipment to see if it will withstand the pressure. For the PVA consolidated specimens that are flaking, you can try reducing the surface coating with cloth poultices using acetone. Experiment on didactic pieces, if you have any. It won't be possible at this point to remove the consolidant that's penetrated into the bone without destroying the specimen. If you can't reduce the surface coating without more damage. your best course is to stabilize the surface flaking. I would suggest using Paraloid B-72 in acetone, 5% w/v in acetone to tack down the lifting areas. Let me know if you have any questions. -- Paul S. Storch Project Specialist III /Sites Collections and Exhibits Liaison Facilities-Historic Properties Department Facilities and Risk Management Division Minnesota Historical Society 345 Kellogg Blvd. West Saint Paul, MN 55102-1906 (651) 259-3257 [email protected] Visit Historic Sites! www.mnhs.org ****** Unsubscribe by sending a message to [email protected] Archives through August 2016 at http://cool.conservation-us.org/byform/mailing-lists/cdl/ Archives from September 2016 onward at https://www.mail-archive.com/[email protected]/
