Tusionite
Encyclopedia
Tusionite is a rare colorless to transparent to translucent yellow brown trigonal borate
mineral
with chemical formula
: MnSn(BO3)2. The mineral is composed of 18.86% manganese
, 40.76% tin
, 7.42% boron
, and 32.96% oxygen
. It is a late stage hydrothermal mineral and occurs rarely in granite
pegmatite
s in miarolitic cavities.
Tusionite was named for the location where the mineral was first discovered and described in 1983 in the Tusion River Valley in the Pamir Mountains
of Tajikistan
. Tusionite has also been reported from Recice
in the Czech Republic
and in pegmatites at Thomas Mountain, Riverside County, California
.
Borate
Borates are chemical compounds which contain oxoanions of boron in oxidation state +3. The simplest borate ion, BO33−, has a trigonal planar structure. Other borates are made up of trigonal BO3 or tetrahedral BO4 structural units, sharing oxygen atoms...
mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
with chemical formula
Chemical formula
A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....
: MnSn(BO3)2. The mineral is composed of 18.86% manganese
Manganese
Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
, 40.76% tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
, 7.42% boron
Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...
, and 32.96% oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
. It is a late stage hydrothermal mineral and occurs rarely in granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
pegmatite
Pegmatite
A pegmatite is a very crystalline, intrusive igneous rock composed of interlocking crystals usually larger than 2.5 cm in size; such rocks are referred to as pegmatitic....
s in miarolitic cavities.
Tusionite was named for the location where the mineral was first discovered and described in 1983 in the Tusion River Valley in the Pamir Mountains
Pamir Mountains
The Pamir Mountains are a mountain range in Central Asia formed by the junction or knot of the Himalayas, Tian Shan, Karakoram, Kunlun, and Hindu Kush ranges. They are among the world’s highest mountains and since Victorian times they have been known as the "Roof of the World" a probable...
of Tajikistan
Tajikistan
Tajikistan , officially the Republic of Tajikistan , is a mountainous landlocked country in Central Asia. Afghanistan borders it to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east....
. Tusionite has also been reported from Recice
Recice
Recice is a settlement in the administrative district of Gmina Osiek, within Starogard County, Pomeranian Voivodeship, in northern Poland. It lies approximately south-east of Osiek, south of Starogard Gdański, and south of the regional capital Gdańsk....
in the Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
and in pegmatites at Thomas Mountain, Riverside County, California
Riverside County, California
Riverside County is a county in the U.S. state of California. One of 58 California counties, it covers in the southern part of the state, and stretches from Orange County to the Colorado River, which forms the state border with Arizona. The county derives its name from the city of Riverside,...
.