Dog Throwing Up Green Mucus

LAPIS-LAZULI - Lazur

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Normally, Lazur, also known as lapis lazuli, form compact masses, impure, minutely granular, colored in deep blue, sometimes tending to purple or bluish-green with gold speckles, due to tiny grains of pyrite included.
How rare is also present in the form of opaque octahedral crystals with vitreous luster.

diagnostic characters

hydrochloric acid is completely decomposed, with evolution of hydrogen sulfide.
exposed to the flame of the torch, first fades, then melts into a white glass.

ORIGIN

is a very common mineral in character, whose genesis seems to be due to contact metamorphism between igneous rocks and limestone dolomite type.

DEPOSITS

The field's oldest and most famous is the Dar-e-sang, in Badakhshan, area located in the Hindu Kush chain, along the border between Afghanistan and Russia.
Other important deposits are in the vicinity of Lake Baikal, in Siberia, where the lapis lazuli, found in limestone rocks, show generally lighter in color than that of Afghanistan to the increased presence of calcite and a lower percentage of pyrite .
then I also remember the deposits in the Chilean Andes.

used in jewelery

Lapis lazuli is a material hard enough da tagliare e particolarmente poroso, ma acquista una buona lucentezza con la lucidatura.
Usato molto in passato per la lavorazione a intaglio, attualmente viene impiegato soprattutto per sfere di collane anche di discrete dimensioni, cabochon e oggetti orna­mentali di vario tipo.

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A precious jewel for a woman ... L E N A ...

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