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Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula Cu Al 6 (PO 4) 4 8 ·4H 2 O.It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.
Shattuckite is a copper silicate hydroxide mineral with formula Cu 5 (SiO 3) 4 (OH) 2.It crystallizes in the orthorhombic – dipyramidal crystal system and usually occurs in a granular massive form and also as fibrous acicular crystals.
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.
The IMA-approved mineral faustite [1] is a member of the triclinic turquoise group of hydrous phosphates with the chemical composition ZnAl 6 (PO 4) 4 (OH) 8 ·4H 2 O. It is named after the American mineralogist and petrologist Dr. George Tobias Faust, who workes with the U.S. Geological Survey (USGS). [2] Some divalent copper generally ...
Lapidaries portrayed "the most common method of medical application" being wearing the stone on one's person in a jewelry setting, for example, in a ring or a necklace or held the stone against the skin. Allowing direct contact between the gem and the skin was encouraged to facilitate the transfer of healing properties. [19]
Most of the white varieties of turquoise are chalk-like with a Mohs hardness of 1, and are not as hard or durable as howlite, and subsequently require stabilization in order to be used in jewelry, which has resulted in howlite being more popular for use in jewelry than the artificially stabilized white forms of the mineral turquoise. [9]
A recent study compared the unhealthiest fast-food chicken sandwiches by scoring calories, saturated fat, sugar, and sodium. Find out where the most popular fast food chains ranked. Here are 20 ...
Dispersion: 0.017 [1]: Ultraviolet fluorescence: Pink stones; inert to very weak red to violet in long and short wave [1]: Absorption spectra: Strong narrow band at 498 nm, and almost complete absorption of red down to 640 nm in blue and green stones; red and pink stones show lines at 458 and 451 nm, as well as a broad band in the green spectrum [1]