Amphiboles (silicates): Cummingtonite
Diagnostic card.
On the picture. Samples of cummingtonite with biotite from Cummington, Massachusetts, USA.
(Mg, Fe) 7 (OH) 2 (Si 4 O 11 ) 2
Singonia monoclinic
Hardness 5-6
Specific weight 3,1-3,4
Cleavage along the prism, good
Color grayish green, brown
Gloss is glassy, silky
It is represented by light brown fibrous aggregates, in appearance resembling asbestos (serpentine-asbestos), but with glass shine. The color is grayish-green or brown.
Diagnostic signs.
Does not dissolve in acids. In the flame of the candle melts, turning into black glass.
Origin.
The mineral is characteristic of rocks of regional contact metamorphism; But can also occur in some igneous rocks and in ore deposits.
Place of Birth.
Together with the anthophyllite was found in association with amphiboles and grenades in Isopaa in Finland. It is present in Ringing in New Zealand, Dowering in Australia, Krivoy Rog in Ukraine, Rockport in Massachusetts, in shale and granulites in Sutherland in Scotland.
A number of cummingtonite.
Includes grunerite, which is a species more rich in iron and magnesium.
- Ghetchellit - "New Almaden blend" - arsenide and antimony sulfide (modern sulfosol)
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- Gold - yellow dangerous and poisonous metal of modern accurate digital and cable technologies
- Sulfur is a golden-yellow toxic substance and a sign of active volcanic activity
- Cadmium is an undisputed toxic silvery metal unknown to a wide range of people
- Lead - a toxic gray imitator of metallic silver and toxic metal blende
- Arsenic is a classic poison of medieval and modern poisoners and medicine in medicine
Poisonous and radioactive dangerous stones and minerals
** - poisonous stones and minerals (mandatory check in the chemical laboratory + explicit indication of toxicity)
** - radioactive stones and minerals (mandatory check on the standard dosimeter + ban on open sales in case of radioactivity exceeding 24 milli / g / h + additional measures of population protection)
Catalog of minerals and semi-precious stones of the world by groups
** - poisonous stones and minerals
** - radioactive stones and minerals
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