Scorzalite

minerals

berlinite

trolleite

lazulite

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Formula: Fe2+Al2(PO4)2(OH)2
Anhydrous phosphate containing hydroxyl, lazulite group, and forms a series with lazulite
Specific gravity: 3.33
Hardness: 6
Streak: White to light blue
Colour: Dark azure blue, green-blue, blue-green
Environments

Pegmatites
Metamorphic environments

Lazulite and scorzalite occur as secondary minerals in pegmatites in many regions where metamorphic rocks are intruded by granitic rocks. The metamorphic rocks commonly exhibit high-grade metamorphism. The phosphate minerals intimately associated with lazulite or scorzalite in these regions include fluorapatite, lacroixite, triphylite, wyllieite, wagnerite, berlinite, svanbergite, attakolite, trolleite, augelite, brazilianite and souzalite. Admixed aluminum-rich minerals include kyanite, andalusite, sillimanite, corundum, pyrophyllite, spinel, dumortierite and almandine - spessartine garnet. Other associated minerals are quartz, microcline, muscovite, beryl, tourmaline, rutile, ilmenite, hematite, magnetite, pyrite, chalcopyrite, calcite, siderite and aragonite.
Lazulite and scorzalite are common accessory minerals in (1) mica deposits in the United States, Brazil and eastern Siberia, (2) andalusite deposits in California and Armenia, (3) diamond and gold placers in Brazil, (4) corundum variety sapphire placers in the Himalaya Mountains and (5) quartz crystal deposits in the Ural Mountains.
Quartz-rich veins and dikes containing lazulite or scorzalite occur in quartzite, quartzitic schist and gneiss. The lazulite or scorzalite occurs as irregular masses or, rarely, as faceted crystals in druses. Andalusite, rutile, kyanite, muscovite and pyrophyllite are common mineral associates.
Lazulite or scorzalite in granitic pegmatites selectively occur in the border zone rather than in the central zone. A number of other phosphate minerals, plagioclase, quartz, muscovite, tourmaline and beryl are the common mineral associates in this environment (AM 35.1-18, HOM, Mindat).

Localities

At the type locality, the Córrego Frio mine, Linópolis, Divino das Laranjeiras, Minas Gerais, Brazil, scorzalite occurs in a pegmatite principally in the border zone and outer margin of the crystal cavity zone. The largest mass of scorzalite observed is about 7 cm across, and the masses are rarely free from admixed souzalite (AM 34.83-93).

At the Victory Mine, Custer, Custer Mining District, Custer county, South Dakota, USA, mica-bearing pegmatite is internally divided into a wall zone composed essentially of plagioclase, quartz, and muscovite, and a core of feldspar variety perthite and quartz. Scorzalite was found principally in the wall zone. In all the hand specimens available, scorzalite occurs only in pegmatite with quartz, plagioclase, muscovite, tourmaline and triphylite. The scorzalite is massive and intimately intergrown with the tourmaline, triphylite, and muscovite (AM 34.685-687).

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