Devilline is a

sulfate mineral The sulfate minerals are a class of minerals that include the sulfate ion () within their structure. The sulfate minerals occur commonly in primary evaporite depositional environments, as gangue minerals in hydrothermal veins and as secondary mine ...

with the chemical formula CaCu₄(SO₄)₂(OH)₆•3H₂O. The name originates from the French chemist's name,

Henri Etienne Sainte-Claire Deville Henri is an Estonian, Finnish, French, German and Luxembourgish form of the masculine given name Henry. People with this given name ; French noblemen :'' See the 'List of rulers named Henry' for Kings of France named Henri.'' * Henri I de Montm ...

(1818–1881). Devilline crystallizes in the

monoclinic In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic s ...

system. Crystallographically, it contains three vectors of unequal lengths and two pairs of vectors are perpendicular while the other pair makes an angle other than 90°. Devilline is prismatic and belongs to the crystal class 2/m. This mineral belongs to the space group P 2₁/c. Devilline is an anisotropic mineral, meaning that the mineral has different properties in different directions. Optically, this mineral is biaxial negative, meaning that it contains two optic axes. Devilline has a moderate mineral relief. Mineral relief refers to the way a mineral appears to stand out when viewed under polarized light and it is dependent on the mineral's index of refraction. Devilline is a rare and unusual secondary mineral found in the

oxidized Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...

portions of

copper sulfide Copper sulfides describe a family of chemical compounds and minerals with the formula CuxSy. Both minerals and synthetic materials comprise these compounds. Some copper sulfides are economically important ores. Prominent copper sulfide mineral ...

ore deposit Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 April ...

s. Because Devilline occurs in such oxidation zones, this mineral often is of post-mining origin. Devilline is found in mines all around the world.

Devilline group

Devilline group minerals are monoclinic sulfates.

References

Calcium minerals Copper(II) minerals Sulfate minerals Monoclinic minerals Minerals in space group 14 {{sulfate-mineral-stub