Chrysocolla
Chrysocolla is a mineral from the Silicate group, Phylosilicate subgroup. It is a hydrated copper silicate with the formula (Cu,Al)4H4 (OH)8 Si4 O10 ·nH2O), sometimes called "siliceous copper".
We can observe it forming incrustations in the rock, in stalactitic masses or filling veins, with an intense bright green to bluish color. The highest purity specimens, once polished, become highly appreciated ornamental stones.
Training environment
Chrysocolla is a mineral of secondary formation , is formed in the upper part of copper deposits, the so-called oxidation zone, so it is easy to find chrysocolla associated with other copper minerals such as cuprite, azurite, malachite and many other secondary copper minerals. This characteristic made it used by ancient miners as an indicator on the surface of copper deposits.
Chrysocolla is generally found forming botroidal or rounded masses and crusts, or vein pluggings. Due to its light color, it is sometimes confused with turquoise.
Among the places with the largest Chrysocolla deposits located are Israel, the Democratic Republic of the Congo, Chile, Cornwall in England, and Arizona, Utah, Idaho, Peru, New Mexico and Pennsylvania in the United States.
Etymology and history
Its name comes from the Greek chrysos, "gold", and kolla, "glue,", in allusion to the name of the material they used to solder gold in ancient Greece. The first chronicles that speak of its use date it around the year 315 BC. C. Theophrastus alludes to chrysocolla as an element to solder gold.
Controversy: Is chrysocolla a mineral?
A 2006 study has provided evidence that chrysocolla could be a microscopic mixture of the copper hydroxide mineral spertiniite, amorphous silica (probably chalcedony or opal), and water.