Helpful Information: Turquoise is a gem that has been revered and worn by cultures all over the world since at least 4,000 B.C. It is still much beloved worldwide because of its blue to blue-green color which is complimentary to a setting of either silver or gold. It is often found with matrix, the host rock that turquoise is associated with, and this causes the veining found throughout the gem. Because turquoise has been popular for so long, there have been many treatments and many imitations developed over the years. It is very important to deal with someone who knows and appreciates fine turquoise. The United States is fortunate in that there are several states that produce good turquoise; Arizona, Nevada, New Mexico, and Colorado. Although 90% of the turquoise on the market today has had some treatment, there is about 10% that when mined is hard and dense enough and does not need any help. Often treatment is required because the turquoise is chalky and very porous and would not take a good polish otherwise. Top grade turquoise does not have this problem. Look for it in one of a kind custom designs. It will not be found in mass produced and standard looking turquoise jewelry. Treat turquoise with the respect it deserves. Keep it away from oils, chemicals, and other agents that can discolor it.