Bellite
Encyclopedia
Bellite is a mixture of minerals from Tasmania
which forms attractive orange red crystals. Its empirical formula, PbCrO4,AsO4,SiO2 suggests a rather complex mixture of chromate
s and silicate
s of lead
and arsenic
. It is considered to be possibly, a mixture of crocoite
, mimetite
and quartz
.
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
which forms attractive orange red crystals. Its empirical formula, PbCrO4,AsO4,SiO2 suggests a rather complex mixture of chromate
Chromate
Chromate salts contain the chromate anion, CrO42−. Dichromate salts contain the dichromate anion, Cr2O72−. They are oxyanions of chromium in the oxidation state +6. They are moderately strong oxidizing agents.- Chemical properties :...
s and silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...
s of lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
and arsenic
Arsenic
Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...
. It is considered to be possibly, a mixture of crocoite
Crocoite
Crocoite is a mineral consisting of lead chromate, PbCrO4, and crystallizing in the monoclinic crystal system. It is sometimes used as a paint, being identical in composition with the artificial product chrome yellow. It was discovered at Berezovsky deposit near Ekaterinburg in the Urals in 1766;...
, mimetite
Mimetite
Mimetite, whose name derives from the Greek Μιμητής mimethes, meaning "imitator", is an arsenate mineral which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name is a reference to mimetite's resemblance to the mineral pyromorphite...
and quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
.