Metatorbernite (or meta-torbernite) is a
radioactive phosphate mineral, and is a
dehydration pseudomorph of
torbernite. Chemically, it is a
copper uranyl phosphate and usually occurs in the form of green platy deposits. It can form by direct deposition from a
supersaturated
In physical chemistry, supersaturation occurs with a solution when the concentration of a solute exceeds the concentration specified by the value of solubility at equilibrium. Most commonly the term is applied to a solution of a solid in a liqu ...
solution, which produces true crystalline metatorbernite, with a dark green colour, translucent
diaphaneity, and vitreous lustre. However, more commonly, it is formed by the dehydration of torbernite, which causes internal stress and breakage within the
crystal lattice
In geometry and crystallography, a Bravais lattice, named after , is an infinite array of discrete points generated by a set of discrete translation operations described in three dimensional space by
: \mathbf = n_1 \mathbf_1 + n_2 \mathbf_2 + n ...
, resulting in crystals composed of microscopic powder held together using
electrostatic force, and having a lighter green colour, opaque diaphaneity, and a relatively dull lustre. As with torbernite, it is named after the
Swedish
Swedish or ' may refer to:
Anything from or related to Sweden, a country in Northern Europe. Or, specifically:
* Swedish language, a North Germanic language spoken primarily in Sweden and Finland
** Swedish alphabet, the official alphabet used by ...
chemist Torbern Bergman. It is especially closely associated with torbernite, but is also found amongside
autunite,
meta-autunite and
uraninite.
References
Uranium minerals
Uranyl compounds
Copper(II) minerals
Phosphate minerals
Radioactive minerals
Tetragonal minerals
Minerals in space group 85
Uranium(VI) minerals
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