My specialty is cutting Sapphires and am busy cutting away on some beautiful Australian top color blues and blue/greens right now. I also have lots of cutting ahead of me, as I have Montana sapphires on the dop, just waiting for me….. Too many stones, too little time!
When we got our Tunduru/Songea Sapphires, I went through them all, checking out the quality, what silk was in them, what percentage couldn’t be used and weight. What I discovered was that we got lots of color change stones.
My method when cutting these Sapphires is to roll the stone on a flat surface and whatever side comes to rest down, becomes the table of the stone. I cut crown first, which is unusual in this time of “meetpoint” faceting, but if it was good enough for the Diamond Cutters, it’s good enough for me.
By cutting crown first, I have been able to up my recovery to 15 to 20% more than with the meetpoint method cutting Pavilion first. Many people disagree, but it works for me !!!
The Tunduru/Songea Sapphires we got go from a dark purple under Halogen to a Kashmir blue under Fluorescent to a beautiful blue/green in daylight. Sapphires are what I enjoy cutting best, Beryl next and Kunzite least !!!
I also use a piece of clear optical quartz when perfecting a new design. Some people feel that using Citrine, Smoky Quartz or Amethyst is justifiable for this, but I took some advice from some Great People (Bob Johnson, Bob Wilson and Bill LaCombe) when I was just getting started, and that was to buy the best quality rough I could afford.
As a result, we don’t use Citrine, Smoky or Amethyst, as the rough we have is too fine quality to practice on. We have also used clear marbles, which are great to practice on, glass, and some Russian Purple Fluorite, because it’s soft and easy to see where you’re off on your cuts.
However, it’s really messy and you get purple all over everything. I don’t use that much anymore. I usually give that to my beginner students to get them started !! This way they don’t have to press as hard and can see their meets very clearly.
I can’t stress enough for faceters to learn to cut both ways, crown first, pavilion first as it makes you more confident and more proficient at your cutting.