What are the natural colours of chalcedony?
The natural color of chalcedony is usually blue. However I have seen natural chalcedony of all sorts of colors. However dark colors of chalcedony are a sign of a dye treatment. Most of the intense pink, blue, orange, yellow, purple stones are all dyed chalcedony. Most natural ones come from Brazil. Some turkey miners have been getting nice pastel colors of chalcedony.
Thank you for the information.