Amate kits are made of a base of German silver, overlaid with sterling silver.

How to care for your Amate jewellery-
Your pewter pendants, ring, bracelet or pendant kit can be cared for with a soft jewellery cloth.  Do not use liquid jewellery cleaner.
Polymer clay can be baked directly in your piece in the oven. 
If using PMC (precious metal clay), bake your PMC separately from the piece as the PMC requires a much higher temperature.  When your PMC is done, you can adhere it into your jewellery piece.

The pendant bails have a very generous opening on them and will accomodate chain, fibers, ribbon, etc. 
The pendant wells, in most instances, are a little more than 1/4" deep.  This allows for the application of polymer clay, collages, UTEE (ultra thick embossing enamel), photos, precious metal clay, small embellishments and many other things.