Bazzite

bazzite

laumontite

bavenite

beryllium

Images

Formula: Be3(Sc,Fe3+,Mg)2Si6O18.Na0.32.nH2O
Cyclosilicate (ring silicate), beryl group, beryllium-bearing mineral
Crystal System: Hexagonal
Specific gravity: 2.77 to 2.8 measured, 2.82 calculated
Hardness: 6½ to 7
Streak: White
Colour: Deep blue or other shades of blue, blue-green
Common impurities: Fe,Mn,Mg,Li,Na,K,Rb,Cs
Environments

Plutonic igneous environments
Pegmatites
Hydrothermal environments

Bazzite is found in miarolitic cavities in granite, granite pegmatites and in Alpine veins associated with pegmatitic minerals.
The blue colour is caused by appreciable iron contents, and the intensity of the colour is determined by the ratio of Fe2+ to Fe3+ (Mindat).

Localities

At the type Locality, the Seula mine, Mount Camoscio, Oltrefiume, Baveno, Verbano-Cusio-Ossola Province, Piedmont, Italy, bazzite occurs in miarolitic cavities in granite, associated with quartz, orthoclase, muscovite, laumontite and albite (HOM).

At the Heftetjern pegmatite, Tørdal, Drangedal, Vestfold og Telemark, Norway, bazzite occurs in the granite pegmatite associated with beryl and bavenite (HOM).

At Val Strem, Tujetsch, Surselva Region, Grisons, Switzerland, bazzite occurs in alpine veins associated with quartz, hematite, calcite, chlorite, albite and fluorite (HOM).

At the Farview area, Mount Rosa, El Paso county, Colorado, USA, beryl is absent, but late-stage to secondary beryllium-bearing minerals are present. Bazzite occurs in small vugs within a quartz vein, associated with pyrite, magnetite and goethite (R&M 95.3.271-272).

In New Hampshire, USA, bazzite has been reported from the Government pit Albany, North Sugarloaf Mountain Bethlehem and Iron Mountain mine Bartlett. The bazzite occurs in NYF pegmatites as minute, transparent, intensely blue crystals less than 2 mm long. The crystals are found in small miaroles associated with quartz, albite and sometimes other beryllium species (R&M 97.2.211-212).

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