Cut Stones Cost
As far as the cost of blue Topaz, I find that most of the rough sells for about what the cut stones cost. There are a lot of possible reason for this phenomenon, here are a few. The cutting houses are buying clear Topaz by the ton and getting the rough very cheap. Rough is sold by quantity, especially materials like Topaz that are in abundance. Of course buying tons of Topaz does cost millions of dollars, but they are working on a global scale.
Another reason. Blue Topaz is cheap is that the cutting houses are connected directly to the mines and often the governments of the producing counties. They have sweetheart deals that the average rough dealer cannot get. It is big business, I would if I could too.
Cutting houses often own their own treatment (nuke) facilities for making blue Topaz out of clear white Topaz. Because they own the treating plants, they are getting the treated material