Not all stones will be the same height, so keep this in mind when ordering in multiples. Each stone is unique and can have inclusions.
NOTE: Follow the industry stone charts to see what natural stones can be fired. Some of them can and some cannot. There is no difference in composition from one particular stone to another (sunstone to sunstone, etc), however, the stone can crack due to inclusions. There is no guarantee as to whether a stone will survive firing based on inclusions. Things can happen during firing. However, sapphires, rhodolite, garnets can be fired to 1650F. Other stones like moonstone and sunstone can be fired to certain temperatures. Again, consult the industry charts. Firing chart coming soon.