Chambersite is a
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 ...
borate mineral
The borate minerals are minerals which contain a borate anion group. The borate (BO3) units may be polymerised similar to the SiO4 unit of the silicate mineral class. This results in B2O5, B3O6, B2O4 anions as well as more complex structures wh ...
with formula . It is a member of the borate mineral series
[Grice ''et al.'', 2005] that includes other minerals such as
ericaite () and
boracite
Boracite is a magnesium borate mineral with formula: Mg3 B7 O13 Cl. It occurs as blue green, colorless, gray, yellow to white crystals in the orthorhombic - pyramidal crystal system. Boracite also shows pseudo-isometric cubical and octahedral fo ...
().
[Yawn ''et al.'', 1997] When chambersite was first discovered, it was the second chemical analogue of boracite to be found in nature.
[Honea ''et al.'', 1962] It was discovered as a mineral at Barber's Hill
salt dome
A salt dome is a type of structural dome formed when salt (or other evaporite minerals) intrudes into overlying rocks in a process known as diapirism. Salt domes can have unique surface and subsurface structures, and they can be discovered usin ...
in
Texas
Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...
in 1957 and in 1971 at the
Dongshuichang deposit in
Jixian,
Tianjin
Tianjin (; ; Mandarin: ), alternately romanized as Tientsin (), is a municipality and a coastal metropolis in Northern China on the shore of the Bohai Sea. It is one of the nine national central cities in Mainland China, with a total popu ...
,
China.
[Fan ''et al.'', 1999] Chambersite occurs associated with the
evaporite
An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocean ...
minerals
halite
Halite (), commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride ( Na Cl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, p ...
,
anhydrite
Anhydrite, or anhydrous calcium sulfate, is a mineral with the chemical formula CaSO4. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the ...
, and
gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywal ...
.
Chemical and physical properties
When chambersite was first discovered in Barber's Hill, the dominate form was the positive
tetrahedron
In geometry, a tetrahedron (plural: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. The tetrahedron is the simplest of all th ...
, but single morphological twinned crystal was found with interpenetrating tetrahedrons with the twinning axis.
The ore discovered in China had formed in high grades that are spindle and granular that form micritic
aggregates because the
boron present is very pure and in low grades that had formed spheroids that are radially oriented.
When chambersite in China was compared it had the same chemical
oxide ratio as the samples found in Barber's Hill.
Geologic occurrence
Chambersite minerals were first found in 1957 in
brine returns from a gas storage well in the Barber's Hill salt dome. The age of the dome is not definitely known, but it is at least dates back to the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
and possibly upper
Jurassic
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...
.
Other chambersite deposits with this similar geologic occurrence can be found in the area of the
Gulf Coast
The Gulf Coast of the United States, also known as the Gulf South, is the coast, coastline along the Southern United States where they meet the Gulf of Mexico. The list of U.S. states and territories by coastline, coastal states that have a shor ...
of
Mexico
Mexico (Spanish: MĂ©xico), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
.
[Smith ''et al.'', 1994] The Venice dome in
Plaquemines Parish, Louisiana is a site that has a shallow piercement salt dome, LPG storage and brine production.
Other chambersite deposits can be found in the Penobsquis deposit in Southern
New Brunswick
New Brunswick (french: Nouveau-Brunswick, , locally ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. It is the only province with both English and ...
,
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, which has high grade salt deposits as well as a significant borate mineral concentration, including chambersite.
Other chambersite deposits can be found as ores in
Ji County, Tianjin
Jizhou District (), formerly a county known as Ji County, is a district in the far north of the municipality of Tianjin, People's Republic of China, holding cultural and historical significance (''e.g''., the Buddhist Temple of Solitary Joy).
O ...
,
China, an area that is known to have had much
magnetic activity and submarine
volcanism
Volcanism, vulcanism or volcanicity is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics, and volcanic gases erupt through a break in the surface called a ...
in a subtidal
lagoon
A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') ...
.
Special characteristics
Chambersite was named after the county where it was first discovered,
Chambers County, Texas
Chambers County is a county in the U.S. state of Texas. As of the 2020 census, its population was 46,571. The county seat is Anahuac.
Chambers County is one of the nine counties that comprise Greater Houston, the Houston– The Woodlands†...
, US.
Optical examination and x-ray powder diffraction indicated the mineral to be related to boracite but different from any other published description.
See also
*
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 ...
References
* Anthony, J.W., Bidideaux, R., Bladh, K. and Nicholas, M. (2003
Chambersite Mn3B7O13Cl Handbook of Mineralogy. Mineral data publishing
* Fan, DL, Yang, PJ, and Wang, R (1999) Characteristics and origin of the Middle Proterozoic Dongshuichang chambersite deposit, Jixan, Tixian, Tianjin, China. Ore Geology Reviews, 15, 15-29.]
* Grice, J. D., Gault, R. A., van Velthuizen, J. (2005) Borate minerals of the Penobsquis and Millstream deposit, southern New Brunswick, Canada. Canadian Mineralogist, 43, 1469-1488.]
* Honea, Russell M., Beck, Frank R. (1962
Chamersite, a new mineral American Mineralogist
''American Mineralogist: An International Journal of Earth and Planetary Materials'' is a peer-reviewed scientific journal covering the general fields of mineralogy, crystallography, geochemistry, and petrology. It is an official journal of the Min ...
, 47, 665-671.
* Smith, Arthur E., Jr. (1994) Louisiana mineral locality index. Rock and Mineral, 69, 156-162.]
* Yawn, B., Simmons, W. B., Falster, A. U. (1997) Chemical Zonation in Chambersite and Boraciate from salt domes in the Gulf Coast region. Rock and Minerals, 72, 192.
{{Commons category
Tektoborates
Halide minerals
Manganese(II) minerals
Orthorhombic minerals
Minerals in space group 29
Borate chlorides