The distinctive silver jewellery produced by the Navajo and other Southwestern Native American tribes today is a rather modern development, thought to date from around 1880 as a result of European influences. It has the appearance of yellowish-grey very brittle mass of crystalline structure. Since at least the First Dynasty (3000 BCE) in ancient Egypt, and possibly before then, turquoise was used by the Egyptians and was mined by them in the Sinai Peninsula.
The Ancestral Puebloans (Anasazi) of the Chaco Canyon and surrounding region are believed to have prospered greatly from their production and trading of turquoise objects.
The turquoise is found in sandstone that is, or was originally, overlain by basalt. The various metaphosphate ions (which are usually long linear polymers) have an empirical formula of (PO3)− and are found in many compounds. Such material is sometimes described as "spiderweb matrix"; it is most valued in the Southwest United States and Far East, but is not highly appreciated in the Near East where unblemished and vein-free material is ideal (regardless of how complementary the veining may be). While strong sky blues remain superior in value, mottled green and yellowish material is popular with artisans. These names are also used for salts of those anions, such as ammonium dihydrogen phosphate and trisodium phosphate. , The goddess Hathor was associated with turquoise, as she was the patroness of Serabit el-Khadim, where it was mined. It was apparently unknown in India until the Mughal period, and unknown in Japan until the 18th century.
Iran has been an important source of turquoise for at least 2,000 years. Her titles included "Lady of Turquoise", "Mistress of Turquoise", and "Lady of Turquoise Country". Climate factors appear to play an important role as turquoise is typically found in arid regions, filling or encrusting cavities and fractures in typically highly altered volcanic rocks, often with associated limonite and other iron oxides.
These phosphorylation and dephosphorylation reactions are the immediate storage and source of energy for many metabolic processes. Turquoise, already favoured for its pastel shades since around 1810, was a staple of Egyptian Revival pieces.
That's how you get Cu3(PO4)2. However, turquoise is often recovered as a byproduct of large-scale copper mining operations, especially in the United States.
While nearly every county in the state has yielded some turquoise, the chief producers are in Lander and Esmeralda counties.
what is ?) In mineralogy and geology, phosphate refers to a rock or ore containing phosphate ions.
The term also refers to the trivalent functional group OP(O-)3 in such esters.
Gem-quality material, in the form of compact nodules, is found in the fractured, silicified limestone of Yunxian and Zhushan, Hubei province.
Calibrated stones—that is, stones adhering to standard jewellery setting measurements—may also be more sought after. in many tobacco farming operations in the southeast US). Turquoise is treated in many different ways, some more permanent and radical than others.
Phosphates are the naturally occurring form of the element phosphorus, found in many phosphate minerals.
Despite its low hardness relative to other gems, turquoise takes a good polish. Copper (II) has 2+ charge. Typically the form is vein or fracture filling, nodular, or botryoidal in habit.  In the ancient Persian Empire, the sky-blue gemstones were earlier worn round the neck or wrist as protection against unnatural death. 4H2O.
Arizona is currently the most important producer of turquoise by value. Turquoise may also be peppered with flecks of pyrite or interspersed with dark, spidery limonite veining. The lustre of turquoise is typically waxy to subvitreous, and its transparency is usually opaque, but may be semitranslucent in thin sections.