Consolidating bone

Sayde Sortibran Cardenas <sortibran [at] yahoo__com> writes

>My name is Sayde Sortibran, and I studied restauration in Mexico
>City. I need information about how I can consolidate  bone, it is a
>mamut bone.

May I add a word of caution about using poly(vinyl acetate) (PVA) to
consolidate bone. I have come across examples of PVA crosslinking
after only a few years: discolouring, shrinking and causing problems
with salt migration. PVA can release acidic compounds as it
deteriorates, which could cause increased damage to the bone.

I prefer to use acrylic copolymer resins which are more stable
(Fehler Class A) and which avoid the problems with plasticisers. For
dry bone I use Paraloid (Acryloid) B72, a mixture of ethyl
methacrylate and methyl acrylate dissolved in acetone or a suitable
mix of solvents. For damp or wet bone I have used a colloidal
dispersion of a similar resin, Primal (Acrysol) WS-24 in water.

I have used these materials on sub-fossil bone as well as
archaeological remains,with excellent results. Items treated this
way 25 years ago are still in excellent condition.

I would strongly recommend searching the Archives of Cons DistList
as the subject of consolidating bones has been dealt with in useful
detail in recent years, including considerations of the reasons for
treating bone and the analytical problems this may cause.

The most useful article on this subject is: "The consolidation of
archaeological bone" by Stephen P. Koob in Adhesives and
Consolidants, Preprints of the Paris Congress, Sept 1984 p. 98-102

Helena Jaeschke
Archaeological Conservator, UK


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                  Conservation DistList Instance 17:9
                  Distributed: Thursday, July 3, 2003
                        Message Id: cdl-17-9-002
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