Terms to know when talking about turquoise (spelling ends with an “e” is the more excepted European modernization-without the “e” is the old west spelling).
Dyed: pigment is added to the rock to improve the color.
Reconstituted: When chips or fragments are cemented together to form.
Stabilized: When low grade or fractured pieces or chalk turquoise is reinforced so that it can withstand the cutting & polishing process and the stress of being worn. Often low grade material can be stabilized to appear high grade.
Enhanced: Patented process in which low grade material is improved.
Oiled or Waxed: When turquoise is soaked or heated in oil or paraffin wax, often with dye, to improve the color.
When purchasing turquoise make sure you get in writing what treatments have been preformed on your piece. Also keep in mind that most turquoise today has had some improvement preformed on it. The old hard turquoise is hard to come by and most of the modern material has to be treated.