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Helvite
Chemical Formula	Mn4Be3SiO43S
Species	Silicates
Crystal System	Isometric
Mohs Scale	6
Specific Gravity	3.2-3.44
Color	Golden yellow, brown, red, gray-yellow, yellow-green
Streak	White
Luster	Vitreous, Resinous
Refractive Index	n = 1.728 - 1.749
Diaphaneity	Translucent
Cleavage	Distinct/GoodDistinct on
Fracture	Irregular/Uneven, Conchoidal
Crystal Habit：Tetrahedra, dodecahedra, octahedra
Geological Setting：Granites, pegmatites, gneisses, contact zones, skarns.

Helvine, HELVITE: Mn ( 2+ ) 4Be3[S| composition ( SiO4 ) containing BeO 3]; Mn8[BeSiO4]6S2, 11%～ 14%.

Isometric system. Crystal is a tetrahedral or by positive, negative tetrahedron composed of eight surface poly form; usually in the form of an irregular spherical aggregate. Brown red, brown and yellow or red, there is also a green. Vitreous luster to the resinous luster. The hardness of 6 ~ 6.5. Cleavage parallel tetrahedral {111} is not completely. Density of 3.2 g / cm ^3.

In skarn, greisenization granite. Often associated with magnetite and fluorine-containing minerals, such as fluorite, Citrine, zinnwaldite Co.

Is the extraction of beryllium ore mineral. [1]

Basic information

Chemical composition : constituents often contains a certain amount of magnesium and manganese aluminium garnet molecules. Can also be a calcium garnet molecules exist, but the content is not;

Category: silicate mineral - Island silicate - Garnet group;

System and space group: isometric;

The unit cell parameters: a0=1.1526nm;

Almandine morphology: often Chengsi angular three eight surface or diamond surface of the body twelve or two poly shape, aggregates into granular or compact massive;

Color: Brown, dark red to black;

Streak: ibid;

Opacity: opacity;

Gloss: vitreous luster;

Hardness: 7-7.5;

Cleavage and fracture: no cleavage;

Proportion: 4.318g/cm3

Other properties: identification characteristics according to their morphological features of easy identification, but the tribe, a variety of minerals are different from each other, should be carried out in proportion, refractive index, unit cell parameters were measured to determine the;

Genesis and occurrence: is a typical metamorphic mineral, commonly found in a variety of schist, gneiss. Placer is often Youtie aluminum garnet;

Main uses: can be used as abrasive material, transparent color beauty can be used as gemstones;

Famous origin : Asia Alabanda, American North Carolina.

Detailed description

Light garnet in 1817 by Werner named, the English name Helvite is derived from the Greek Helios, sun ( sun ) meaning, alluding to the mineral colors as the sun light. The nature in yellow and yellow-green majority, a reddish brown or yellow brown, if by the late hydrothermal alteration, will produce the phenomenon of bleaching, and in surface by weathering, the color is dark, and the emergence of grey, even the black. HELVITE

HELVITE is a natural rich in beryllium ( Be ) mineral, it and danalite ( Danalite ) and zinc garnet ( Genthelvite ) can form a complete solid solution series, is also one of the sources of beryllium ore. This mineral is mainly produced in granite pegmatite, or in skarn, Germany, Canada, the United States, China, Norway, Finland, Argentina, Russia, Hungary, Chennai and Leah, Mexico, Japan and other countries have output, which is produced in the Quebec province of Canada HELVITE, under ultraviolet radiation, often a deep red fluorescence.

Almandine is purple red spinel variants, garnet if iron aluminum has become almandine. In fact, almandine garnet is one of the most common. Almandine garnet color is usually brown or pale purple, crimson red. Almandine as a gemstone. Almandine, pyrope and Spessartine often occur together.