This precious stone has long been known with a variation of names. In ancient Roman times, it was called callais from the Ancient Greek κάλαϊς as what Pliny the Elder mentioned. Meanwhile, in ancient Aztecs (now Mexico), it was called chalchihuitl.
The current modern name of this precious gemstone, turquoise, was derived from the French turquoise which means “Turkish. The reason behind this is that this mineral was transported to Europe through Turkey which originated from the mines in the ancient Khorasan in Persia (now Iran).
In the United States, this mineral is often mined in the Southwest Regions, particularly in Arizona, Colorado, California, New Mexico, and Nevada. Pre-Columbian Native Americans mined this mineral on the deposits of California and New Mexico with the use of stone tools and aid from some locals and others as far out as central Mexico.
It is thought that the site of the oldest mines was located in Cerrillos, New Mexico. Before the 1920s, New Mexico was the substantial producer of turquoise in the United States; however, mines nowadays are more or less depleted. In California, there is only a single mine located at Apache Canyon that continues to operate commercially.
Generally, turquoise is present as vein fillings and as closely-packed small lumps. However, there are some turquoises discovered with quite an excellent composition that can compete with the Iranian quality both in hue and longevity.
The majority of American turquoise is inferior in quality (often term as chalk turquoise). This may be caused by its above-average levels of iron, causing green and yellows to prevail. Its characteristic consistency of being easily crumbled on its untreated state prevents this type of turquoise to be used in jewelry.
The earliest discovery of a deposit of distinct, single-crystal turquoise occurred in Lynch State, Campbell County, Virginia in 1912. These are quite compact as these crystals are forming a druse over the mother rock. Up until the 1980s, it was widely thought that Virginia was the only place where these types of crystals can be found. Today, there are at least 127 localities that these types of crystals can be mined.
In an aim to recover profits and reach up to the demand, a few American turquoises are primed or enhanced to a certain quality. These enhancements include innocuous waxing and extra controversial processes like dyeing and impregnation. There are several American quarries which generate a high-quality substance that requires no treatment or alterations. Any treatments performed on the precious stone should be divulged to the client.
Throughout history, the majority of prominent ancient cultures favored turquoise due to its pastel shades. The Aztecs (and potentially other Pre-Columbian Mesoamericans), Sovereigns of Ancient Egypt, Persia, the Indus Valley, Mesopotamia, and as far as ancient China such as the Shang Dynasty have adorned turquoise.
Until the 14th century, turquoise did not become significant as an ornamental precious stone in the West, even though it is one of the oldest gems and one of which was introduced to Europe through Turkey alongside various Silk Road novelties. The importance of turquoise was preceded by the decline of the influence of the Roman Catholic Church which tolerated the utilization of turquoise in secular jewelry.
In India, it was seemingly unknown until the rule of the Mughal Empire; whereas in Japan, it remained unknown until the 18th century. The majority of such civilizations have shared and held on a common assumption that this gemstone has certain prophylactic or protective qualities. It was believed that the change in color of the stone is related to the wearer’s health and well-being and defending him from unforeseen forces.