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 ...
iron
Iron () is a chemical element with Symbol (chemistry), symbol Fe (from la, Wikt:ferrum, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 element, group 8 of the periodic table. It is, Abundanc ...
phosphate mineral
Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions, and chloride (Cl−), fluoride (F−), and hydroxide (OH−) anions that also fit ...
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 ...
crystal system
In crystallography, a crystal system is a set of point groups (a group of geometric symmetries with at least one fixed point). A lattice system is a set of Bravais lattices. Space groups are classified into crystal systems according to their poin ...
and typically occurs as elongated and striated slender prisms which may be columnar to fibrous. Its crystals may be pinkish to yellowish brown or red-orange.Handbook of Mineralogy /ref>
It was first described in 1878 for an occurrence in the Branchville Quarry, Branchville, Fairfield County, Connecticut. The name is derived from its resemblance to
triplite
Triplite is a rare phosphate mineral with formula: . It occurs in phosphate-rich granitic pegmatites typically as irregular brown opaque masses. Triplite was first described in 1813 for an occurrence in Chanteloube, Limousin, France.Mindat /ref>
It typically occurs as a
hydrothermal alteration
Metasomatism (from the Greek μετά ''metá'' "change" and σῶμα ''sôma'' "body") is the chemical alteration of a rock by hydrothermal and other fluids. It is the replacement of one rock by another of different mineralogical and chemical co ...
product of primary phosphate minerals in
granite
Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies under ...
triplite
Triplite is a rare phosphate mineral with formula: . It occurs in phosphate-rich granitic pegmatites typically as irregular brown opaque masses. Triplite was first described in 1813 for an occurrence in Chanteloube, Limousin, France.lithiophilite,
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 ...
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 ...
List of minerals
This is a list of minerals for which there are articles on Wikipedia.
Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various ''species''. Within a m ...