When you see a beautifully cut gemstone in a piece of jewelry, its beauty can be captivating. However, very rarely is the sheer skill and risk involved in cutting rare gems appreciated. .
Cutting rare gemstones like tanzanite can be a risky business indeed. So many things can go wrong along the way for the gem cutter. He starts with a simple piece of rough which can be very unexciting to look at and is faced with the task of transforming it into something exceptional. Preforming is the first stage after the rough has been carefully evaluated for inclusions and to ascertain which shape would be best to cut. This is a risky stage as the rough is preformed by hand using a spinning faceting disk. Heat is generated at this point and often non-visible stress fractures can exist within a stone which can cause the stone to shatter or break at this stage.
As you may have guessed , this post is inspired by one such incident in our cutting offices recently which highlights the risks. We were cutting a beautiful and very rare piece of orange Tanzanite which promised to yield over 8 carats of sparkling splendor. Instead, during the performing process the stone, previously flawless started producing thin cracks as we watched. A surreal experience as there is nothing you can do about it. The non-visible stress fracture within the stone, caused by the crystal forming under great pressure, yielded to the heat generated by the performing process and “crazed” – cracked in several different directions.
This problem is not limited to colored gemstones and Diamonds often cause great distress by performing the same trick on their beleaguered cutters! So next time to are looking at a beautiful faceted gemstone, whether Diamond or colored stone, appreciate the great skill and pure miracle that it has survived several hundred million years under pressure and heat in the earth and then successfully navigated the path through the cutting process!
Read more about how gems are cut in our article on Gemstone Cutting
Lapigems Gem Company