WHAT SHOULD I DO WITH THAT STONE???
FIRE OR NOT TO FIRE?
THAT IS THE QUESTION
The following chart explains what to expect if/when a particular
gemstone is fired in place at a given temperature.
Not all stones are listed here, but it gives an artist a good start.
Always pre-test a stone when in doubt.  If this cannot be done and
you value the stone, don't take the chance.  Set the stone after the
metal clay is fired.
Natural stones, whether they can be fired or not, should always be
checked for cracks or inclusions.  Any fault in a gemstone can
result with the stone fracturing when fired in the kiln.
If you would like a full-size copy of the spreadsheet below, contact
me at dr.metalclay@yahoo.com
Cubic Zirconia
Fired in place
Crysacolla
Inserted after firing
Gilson Opal
(man-made stone)
Fired in place