Blue Sapphire Rings vintage

https://p7adhki305.doodlekit.com/blog/entry/5274197/10-principles-of-psychology-you-can-use-to-improve-your-different-kinds-of-diamonds

The heat that produces the diamond may even exceed one,200 degrees Celsius. Nearly anything lower than four hundred degrees Celsius leads to graphite, not diamond. Look at warmth. It corresponds to the heat, the