Manganoan calcite or manganocalcite is a variety of calcite rich in

manganese Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy use ...

, which gives the mineral a pink color.Manganoan Calcite
at Mindat Its chemical formula is . It was first reported from the Banská Štiavnica Mining District, Slovak Republic, but is widely distributed around the world, notably in the Cave of Swords at Naica, Chihuahua, Mexico as well as in

Bulgaria Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...

. Manganoan calcite is sometimes confused with

rhodochrosite Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its (rare) pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. It streaks white, and its Mohs hardness varies bet ...

. The amount of manganese in manganoan calcite varies at different localities, and the mineral forms a

solid solution A solid solution, a term popularly used for metals, is a homogenous mixture of two different kinds of atoms in solid state and have a single crystal structure. Many examples can be found in metallurgy, geology, and solid-state chemistry. The wor ...

series between calcite and rhodochrosite, with the color becoming redder with a higher proportion of manganese.

References

External links

Photo of Manganoan Calcite
at the

University of Delaware The University of Delaware (colloquially UD or Delaware) is a public land-grant research university located in Newark, Delaware. UD is the largest university in Delaware. It offers three associate's programs, 148 bachelor's programs, 121 ma ...

Manganoan Calcite Gallery
Carbonate minerals Calcium minerals Manganese(II) minerals {{Carbonate-mineral-stub