Shells

[Metalfairy]

Can abalone, Paau, Cowrie shells or bone pieces be fired in ACS?

[Metalman]

No - they will break down into, I think calcite, or calcium carbonate.  Basically they will turn white and powdery and fall apart.
You will want to design your pieces around the shell with wire or bezel attachments that you can bend or fold around the shells after firing.  If you put a layer or two of masking tape on the shell, you can balance for the shrinkage of the ACS so that things fit well.  You will probably have to try a few to get the balance right with the layers of masking tape and how you are building your pieces.

[Russ Nobbs]

Paua shell, the bluish New Zealand variety of abalone shell, often has a blue tinted plastic coating which would be destroyed by heat, also. Natural shell "chunks" do not have a coating but many more "finished" pieces do. It enhances the blue color when it is a little pale.

[Metalman]

Following is a quote from a Jewelers forum regarding shells and working with them:   '>
Polishing any shell and especially abalone shell is potentially dangereous. The dust formed in cutting abalone contains a glucamite, a substance that is mistaken by the body for glucose. It can be breathed in and also absorbed through the skin. It can take weeks and months to purge it fom the body. Beside the obvious potential for silicosis of the lungs, this compound can lead to, among other health problems, serious heart problems such as an irregular heart beat. When working with shell, cut it with an abundant water flow. A respirator is also needed. To guard against absorption through the skin wear a long sleeved shirt and latex gloves. Some people say that a chemical guard creme ( I believe Avon makes one) gives sufficient protection to your hands. In any case it would be a good idea to apply such a creme to all exposed skin surfaces. I hope I didn't scare you too much. Abalone is a beautiful shell, which by the way produces gorgeous natural and cultured pearls.
http://www.ganoksin.com/orchid/archive/199908/msg00187.htm