Many stones either semi precious or precious are unable to be fired in place in your metal clay creations. Lab created stones such as cubic zirconias are a good alternative as they are designed to withstand the 900oC. When purchasing Cubic Zirconias to fire in place check that the stones you are buying are fire safe, there are different grades of man made stones and it is wise to double check before firing.
Cubic Zirconia |

