The "odd" gold mineral — Calaverite
For several years, scientists from Germany and Russia have studied calaverite, a mysterious precious metal. Since the days of the gold rush era, gold seekers often find it in the mountains of North America. For many years the incomprehensible stone with golden elements remained an unsolved mystery.
In the photo: calaverite is a telluride of gold with a chemical formula AuTe2, a rare mineral that occurs naturally in the form of crystalline sediments.
People rarely find substantial mineral deposits: compounds of gold with other metals. Yet calaverite is an exception to the rule. Large quantities of this mineral were discovered in the US states, namely in California and Colorado, as well as in Canada, Australia and Romania.
Research conducted by physicists and chemists has proved that calaverite has a very unusual structure that falls outside the scope of crystallography. Gold found in such crystals always has the “wrong” oxidation state of +2, making them chemically unstable. Essentially, this means that the formation of such stones in nature is hardly possible. However, contrary to scientific data on the properties of chemical elements, calaverite does exist!
In the photo: the color of calaverite ranges from silvery white to brassy yellow.
For many years, specialists tried to figure out the properties of this uncommon and complex compound. Scientists concluded that calaverite consists of a mixture of gold atoms with different degrees of oxidation, distributed in a rather odd way throughout the crystal.
Chemists point out that nature "accomplished the impossible" by combining incompatible compounds of gold atoms in one mineral.
Scientific experts were able to uncover an interesting feature of calaverite. They found out that the mineral can be turned into a mega-powerful conductor by adding platinum atoms and compress them under high pressure.
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