GT Advanced Technologies Inc fka GTAT

[Netsurfer]

Virtually all of the electricity was used to heat up and melt the charge of sapphire feed stock. The electricity was run thru a big resistive heater that ran at 2100 +\- C. The heat was dumped to a water heat exchanger.

The heat recovery process was a means to improve electricity utilization.
Instead of dumping the heat to the atmosphere or a water cooling system it was captured and use to "preheat" the and upstream demand for heat. This presupposed that there was electricity available to generate the heat in the first place. I cannot imagine how Apple would have not know and appreciated the difference.

Crackle is commonly used in the industry. It is generally recycled from the left over from coring the boules to get material for LED substrates and or other applications.
If the boule yielded good product recycled Crackle should not be a problem. If a boule was a complete failure of other reasons besides cracking of off axis crystallization it probably should not be recycled.

The kerf waste is not worth the effort to recapture and recycle. It is filled with diamond dust from the saw.....circular of wire.

I do not believe that any industrially grown sapphire gets into the jewelry stream....at least not openly. Synthetic jewelry is a real threat to the industry. There are techniques to alter / enhance the color of natural stones and this is really a taboo even though the stone was natural.

Your thoughts Xena??