A stone will undergo several processes: cleaning, cutting, polishing and then most will also be treated in some way by man. They will be dyed, cavity filled and heat treated which is the more accepted treatment. A high quality untreated stone will be more valuable than a treated one unless the untreated gem is of low quality. You can easily assume that most emeralds for sale are treated because most have tiny fractures and need cavity filling. Find out more about heat treatment.
Other color stone factors that affect price:
• Carat weight
• Treatment (is it treated or untreated)
