Someone gave me some stones he purchased in Cambodia. The numbers on the RI and specific gravity is good, plus they have rough or feathered inclusions. The big issue I have is when I look down through the stone from the table the center is clear. These were sold as pink sapphire, but I think they are poorly cut heat treated?
Hi there, often when I get a piece of corundum rough it has heavy zoning of colour, often a single spot of the best colour at the base of the pavillion wll be enough to flood the whole stone with that colour… when you look closely however you can see where the colour spot is located and its often not the same density/spread throughout… If you do not have a good custody chain record, I would just assume it IS heat treated to be on the safe side if you are going to re-sale the item… best being on the front foot disclosure wise…
I do not think that it would be that unusual for a sapphire to have a clear zone down the axis/crystal
I have a rough sapphire from Qld Australia that is green and has a distinct round light yellow centre down the axis/crystal.