Nosean, also known as noselite, is a mineral of the
feldspathoid
The feldspathoids are a group of tectosilicate minerals which resemble feldspars but have a different structure and much lower silica content. They occur in rare and unusual types of igneous rocks, and are usually not found in rocks containing ...
group with formula:
Na8 Al6 Si6 O24(
SO
4). H
2O. It forms
isometric crystals of variable color: white, grey, blue, green, to brown. It has a
Mohs hardness
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material.
The scale was introduced in 1812 by ...
of 5.5 to 6 and a
specific gravity
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its dens ...
of 2.3 to 2.4. It is
fluorescent
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, ...
. It is found in low-silica
igneous rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma o ...
s. There is a solid solution between nosean and
hauyne, which contains calcium.
It was first described in 1815 from the
Rhineland
The Rhineland (german: Rheinland; french: Rhénanie; nl, Rijnland; ksh, Rhingland; Latinised name: ''Rhenania'') is a loosely defined area of Western Germany along the Rhine, chiefly its middle section.
Term
Historically, the Rhinelands ...
in
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
and named after the German
mineralogist
Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proce ...
K. W. Nose (1753–1835). The mineral is rare but widespread, found in such diverse localities as ocean islands (e.g.,
Tahiti
Tahiti (; Tahitian ; ; previously also known as Otaheite) is the largest island of the Windward group of the Society Islands in French Polynesia. It is located in the central part of the Pacific Ocean and the nearest major landmass is Austra ...
) and the
La Sal Range in
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...
.
References
Webmineral data
Feldspathoid
Sodalite group
Sodium minerals
Aluminium minerals
Sulfate minerals
Cubic minerals
Minerals in space group 215
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