Malachite Chrysocolla (3) Raw Minerals Stones Rocks Collecting

Malachite with Chrysocolla 31-50 gr - cm 3-5 Raw Minerals Stones Rocks for Collection.

Malachite (from the Greek Μολοχίτης, mallow green) is a copper mineral belonging to the class of carbonates (to be precise, it is a cupric carbonate hydroxide), and is effervescent in contact with hydrochloric acid.
It is almost always microcrystalline (weather layer of copper minerals), but it is also found in the form of fibrous layers, in reniform or efflorescent masses. In some cavities malachite can rarely be found in small needle-like crystals.
It originates from the alteration of minerals with the presence of copper.
The deposits are all secondary copper deposits. The largest deposits of malachite are found in Africa, the Democratic Republic of Congo and Zambia, Russia, Australia and the United States.
In Italy the most famous deposit is found on the island of Elba. It is also present in the Lombard Prealps and in the mines of Sardinia.
Due to its beautiful color that goes from light to dark green, and the characteristic growth that makes it characterized by zoning given by nuances of tone, malachite is used in jewelry especially as cabochons and in semi-precious objects. However, being a mineral with low hardness, malachite artefacts can easily scratch and be damaged if used and touched carelessly. It was also used as a pictorial pigment.

Chrysocolla is a useful mineral, although not of great value, for the extraction of copper, of the silicate family.
It occurs in stalactite masses, concretions and microcrystalline earthy encrustations and bright green or bluish, but also encrustations or blue-green spherules.
The mineral is widespread as an alteration product of other copper ores. In particular it is found as a cap of copper minerals, associated with azurite, malachite and cuprite.
When heated it does not melt but becomes blackish and colors the flame green, it is decomposed by hydrochloric acid with separation of gelatinous silica.
The main mines in Italy are located in Sardinia, Elba Island, Piedmont.
In the rest of the world in Arizona, New Mexico, in Chile, Morocco, Zimbabwe, in the Urals in Russia and Congo.