I have just purchased copper clay and did my first firing last week.
The following comes from the sheet in my package.
The pieces must be surrounded by activated carbon in a stainless
steel pan. You spread a 1 inch layer on the bottom of the pan, then
place your pieces at least 1/2 inch apart, more if the pieces are
large. Pour more carbon granules on top, making sure there is a 1/2
inch layer between pieces on top. Fill the stainless steel pan to
top, cover and place in the kiln on stilts to allow good heat
Firing: For pieces that are 6 cards (3mm) thick or less fire as
Ramp at full speed to 1650 F. (900 C) and hold for 2 hours. Total
firing time including warm up will be between 2 1/2 and 5 hours.
Firing thick pieces, or if you plan to fire thicker than 3mm or to
enamel fire the following program
Ramp at full speed to 1650 F (900 C) and hold for 3 1/2 hours. Total
firing time including warm up will be about 4 hours. Thin pieces can
also be fired with the thicker ones.
It is recommended to wear a dust mask when handling the carbon
granules. They are available through Rio Grande.
The above info was in my package of Copper Clay when I bought it,
the pieces I made came out quite well, although one piece should have
been sanded more before I fired it. Hope the above helps.
Make sure the pan you use is stainless steel if you think you have
something around the studio. Many stainless steel pans are plated
over something else and the steel can come off the pan making a real
mess of your kiln.