Formula: Bi2Te2Se
Selenide, bismuth- and tellurium- bearing mineral, tetradymite group
Crystal System: Trigonal
Specific gravity: 8.08 calculated
Hardness: 1½
Streak: Light steel grey
Colour: Silver to tin-white
Common impurities: Fe,S

Hydrothermal environments

Kawazlite is of hydrothermal origin in sulphide/arsenide/selenide veins (Mindat).
It has the curious property of being a topological insulator, and one that is cleaner than synthetic samples. Topological insulators are exotic materials that conduct electricity only along their surfaces, and kawazulite is the first naturally occurring mineral shown to have this property. It could have important applications in the development of quantum computing (Nature doi:10.1038/nature.2013.12569).


The Sue-Dianne deposit, Diane Lake, Mazenod Lake District, Northwest Territories, Canada, is a small uranium-copper deposit. A breccia pipe several hundred metres in diameter, defined by tourmaline veinlets, cuts dacitic ignimbrites. These intensely hematised host rocks are occasionally cut by small veinlets of hematite-pitchblende that also host the bismuth-copper-lead-sulphur-selenium-tellurium mineralisation. Primary and secondary hematite can be distinguished in the veinlets; primary hematite has a platy habit, whereas secondary hematite, produced by the oxidation of magnetite, is present as equidimensional grains with relict magnetite cores. The pipe exhibits extensive superficial copper-rich oxidation products.
The Canadian kawazulite occurs in trace amounts, intimately associated with selenium-bearing covellite. The anhedral grains do not exceed 25 microns in diameter. Kawazulite is also found as submicron inclusions within the covellite; it has either exsolved from covellite or coprecipitated with it.
The first of the minerals to be deposited at Mazenod Lake was magnetite, some primary hematite followed, before the main period of hematite formation and uranium-copper-bismuth-lead-sulphur-selenium-tellurium mineralisation (CM.19.341-348). Other minerals associated with kawazulite include tellurobismuthite, uraninite, hematite and yarrowite (HOM).

At the Suttsu mine, Shiribeshi Subprefecture, Hokkaidō Prefecture, Japan, kawazulite is of hydrothermal origin, ocurring in a quartz vein associated with selenium-bearing bismuthinite, selenium-bearing pavonite, cassiterite, chalcopyrite and pyrite (HOM).

At the type locality, the Kawazu mine, Rendaiji, Shimoda City, Shizuoka Prefecture, Japan, kawazulite is of hydrothermal origin, occurring in a quartz vein in the tellurium deposit as very thin foils up to 4 mm across, with a maximum thickness of 50 microns. Associated minerals include selen-tellurium (HOM, Mindat).

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