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Summary Of: Turquoise
turquoise almost never forms single... of turquoise is typically waxy to subvitreous... of turquoise is approximately 1... Turquoise is insoluble in all but heated... turquoise takes a good polish... Turquoise may also be peppered with flecks of... turquoise apparently forms by the action of percolating acidic aqueous solutions during the... factors appear to play an important role as turquoise is typically found in... In the American southwest turquoise is almost invariably associated with the weathering products of copper sulfide deposits in or around... Typically turquoise mineralization is restricted to a relatively shallow depth of less than 20... Although the features of turquoise occurrences are consistent with a secondary or... difficult to account for the many features of turquoise occurrences by a hypogene process... within turquoise grains that give elevated homogenization temperatures of 90 to 190... Turquoise is nearly always cryptocrystalline and massive and assumes no definite external shape... been traditionally thought to have been altered by turquoise or similar phosphate minerals such as the iron phosphate... Massive turquoise in matrix with... Turquoise was among the first gems to be mined... turquoise is often recovered as a byproduct of large... turquoise was used by the... The turquoise is found in sandstone that is... scale turquoise mining is not profitable today... Bisbee turquoise commonly has a hard chocolate brown coloured matrix... The turquoise occurs as vein or seam fillings... most American turquoise is of a low grade... mines have been worked primarily for their gem turquoise and very little has been recovered as a byproduct of other mining operations... Nevada turquoise is found as nuggets... Most of the turquoise deposits in Nevada occur along a wide belt of... with turquoise from Nevada coming in various shades of blue... Some of this unusually coloured turquoise may contain significant zinc and iron... the total Nevada turquoise production since the 1870s has been estimated at more than 600 tons... scale mining operations continue at a number of turquoise properties in Nevada... crystal turquoise was discovered in... some American turquoise is treated or... reported turquoise found in present... The pastel shades of turquoise have endeared it to many great cultures of antiquity... turquoise did not become important as an ornamental stone in the West until the 14th century... s influence which allowed the use of turquoise in secular jewellery... shared by many of these civilizations held that turquoise possessed certain prophylactic qualities... were used to bond the turquoise to the objects... tribes cherished turquoise for its amuletic use... Among these peoples turquoise was used in... The Persian style and use of turquoise was later brought to... with turquoise usually roughly polished into irregular cabochons set simply in silver... The Egyptian use of turquoise stretches back as far as the... turquoise is most often encountered cut... turquoise is also the traditional... The turquoise is also a stone in the Jewish... Most of these products differ markedly from natural turquoise in both physical and chemical properties... Gilson turquoise is made in both a uniform colour and with black... The most common imitation of turquoise encountered today is dyed... Imitation turquoise is so prevalent that it likely outnumbers real turquoise by a wide margin... An early turquoise mine in the Madan village of Khorasan... Turquoise is treated to enhance both its colour and durability... especially because treated turquoise is usually of a higher grade to begin with... but some turquoise is irradiated to become less... Since finer turquoise is often found as thin seams... it is standard practice that all thinly cut turquoise in the Southwestern United States is backed... Backing of turquoise is not known outside of the... The value of turquoise of the highest quality is not discounted because it is backed and indeed the process... Slab of turquoise in matrix showing a large variety of different colouration... turquoise should not be excessively soft or chalky... in which turquoise is found can often be seen as splotches or a network of brown or black... turquoise is commonly sold at a price according to its physical size in millimetres rather than... applied to most gem turquoise to improve its colour and lustre... the wax or oil is absorbed and the turquoise therefore does not... untreated turquoise will always command a higher price... turquoise is inherently fragile and sensitive to solvents... turquoise should be gently cleaned with a soft cloth to avoid a build up of residue... Turquoise can also be adversely affected if stored in an airtight container... turquoise mineral information and data... Encyclodia Page On: Turquoise
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