Johnbaumite is a
calcium
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...
arsenate
The arsenate is an ion with the chemical formula . Bonding in arsenate consists of a central arsenic atom, with oxidation state +5, double bonded to one oxygen atom and single bonded to a further three oxygen atoms. The four oxygen atoms orien ...
hydroxide
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It ...
mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...
. It was first described in 1980, where it appeared in
Franklin Township,
Somerset County,
New Jersey
New Jersey is a U.S. state, state located in both the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. Located at the geographic hub of the urban area, heavily urbanized Northeas ...
. Johnbaumite was discovered at Harstigen mine in
Sweden
Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...
in the 19th century, but it was described as
svabite.
[ Cristian Biagioni, Marco Pasero; The crystal structure of johnbaumite, Ca5(AsO4)3OH, the arsenate analogue of hydroxylapatite. American Mineralogist 2013;; 98 (8–9): 1580–1584. doi: https://doi.org/10.2138/am.2013.4443]
Etymology
It is named after geologist John Leach Baum (March 15, 1916 – October 16, 2011), who found the original specimen in 1944. He was a significant contributor to the geology and mineralogy of the Franklin deposit, and the Curator Emeritus at the
Franklin Mineral Museum.
See also
*
Hydroxyapatite
Hydroxyapatite (International Mineralogical Association, IMA name: hydroxylapatite) (Hap, HAp, or HA) is a naturally occurring mineral form of calcium apatite with the Chemical formula, formula , often written to denote that the Crystal struc ...
*
Svabite
References
{{Reflist
Further reading
* Biagioni C, Bosi F, Hålenius U, Pasero M (2017) The crystal structure of turneaureite, Ca5(AsO4)3Cl, the arsenate analog of chlorapatite, and its relationships with the arsenate apatites johnbaumite and svabite, American Mineralogist, 102, 1981–1986
* Lee Y J, Stephens P W, Tang Y, Li W, Phillips B L, Parise J B, Reeder R J (2009) Arsenate substitution in hydroxylapatite: Structural characterization of the Ca5(PxAs1-xO4)3OH solid solution, American Mineralogist, 94, 666–675
* Zheng Y, Gao T, Gong Y, Ma S, Yang M, Chen P (2015) Electronic, vibrational and thermodynamic properties of Ca10(AsO4)6(OH)2: first principles study, The European Physical Journal of Applied Physics, 72, 1–7
* Anthony J W, Bideaux R A, Bladh K W, and Nichols M C (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America.
Arsenate minerals
Franklin Township, Somerset County, New Jersey
Calcium minerals
Hexagonal minerals
Minerals in space group 176