VarisciteOften confused with its more common cousin turquoise, this aluminium phosphate mineral is f

VarisciteOften confused with its more common cousin turquoise, this aluminium phosphate mineral is formed by direct precipitation from phosphorous rich waters percolating through aluminium rich country rocks. Usually greener than its cousin, it occurs as nodules, massive infilling in fractures or cavities and crusts. White veins can be an identifying characteristic, as opposed to turquoise’s dark ones (though the material from Nevada has dark veining), and it is a little softer, under 5 on Mohs scale, while its cousin (in gem quality at least as opposed to the stabilised muck going around the markets these days) is slightly over. It is very popular for carvings and ornaments thanks to its softness. Usually opaque to slightly translucent, the common colour is minty green, though many other shades of this hue are known as are violet to reddish specimens when more iron is present in the crystal structure. It was named after the archaic appellation of the Vogtland area of Germany in 1837, but has also been referred to as Utahlite. Found in the USA and Germany, other major localities include Australia, Poland and Brazil. Like its cousin, variscite is porous, and should not be exposed to detergents or chemicals, for example by wearing it while washing up or cleaning your carving. The result can be a permanent and irreversible discolouration.The sliced Utah nodule in the photo is half a metre across.LozImage credit: J. Stubyhttp://www.mindat.org/min-4156.htmlhttp://www.minerals.net/mineral/variscite.aspxhttp://www.minerals.net/gemstone/variscite_gemstone.aspxhttp://webmineral.com/data/Variscite.shtml#.VJlvi_840 -- source link

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