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Gemstones ABC
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A
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A
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Ringsizes
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Andradite
Andradite
Andradite was named James Dwight Dana in 1868 in honor of José Bonifácio de Andrada e Silva [June 13, 1763 Santos, Brazil - April 6, 1838 Niterói, Brazil]
Data:
Formula | Ca3Fe3 + 2 (SiO4) 3 |
Color | Yellow, greenish yellow to emerald green, dark green; brown, brownish red, brownish yellow; greyish black, black |
Gloss | Adamatin, Resiny, Dull |
Hardness | 6.5 - 7 |
Specific Gravity | 3.8 - 3.9 |
Crystal System | Isometric |
Transparency | Transparant, Translucent |
Location | Drammen, Buskerud, Norway |
Andradite is named after José Bonifácio de Andrada e Silva a Brazilian mineralogist. He first described and mentioned what Dana (1868) defined as a sub-variety of andradite.
d'Andrada had previously discovered, in 1800, a yellowish-gray mineral from a mine near Drammen, Buskerud, Norway. He described and called this mineral allochroite (d'Andrada 1800), from the Greek αλλος, another, and χροια, color, as a result of the color change of the heated product with sodium ammonium hydrogen phosphate as a reagent in blowpipe analysis during cooling.
Andradite is found in skarns, (rocks consisting of limestones and silicates, which are formed from carbonates that come into contact with magma), in chlorite slates & serpentinites and in alkaline, titanium-containing igneous rocks
This group consists of: Demantoite, Melanite, Topazolite.
If in stock, you will find my collection of raw Gemstones within this group below. Are you looking for cut Gemstones from, look at ANDRADITE