Bazzite Explained

Bazzite
Category:Cyclosilicate
Formula:Be3Sc2Si6O18
Imasymbol:Bz[1]
Strunz:9.CJ.05
System:Hexagonal
Class:Dihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Symmetry:P6/mcc
Unit Cell:a = 9.521 Å, c = 9.165 Å; Z = 2
Color:Light to dark sky-blue, blue green
Habit:Aggregates of subparallel prisms
Cleavage:Indistinct on
Fracture:Irregular
Tenacity:Brittle
Mohs:6.5–7
Luster:Vitreous
Streak:Pale bluish white
Diaphaneity:Semitransparent
Gravity:2.77–2.85
Opticalprop:Uniaxial (−)
Refractive:nω = 1.622–1.637 nε = 1.602–1.622
Birefringence:0.0210
Pleochroism:O = pale greenish yellow; E = intense sky-blue
References:[2]

Bazzite is a beryllium scandium cyclosilicate mineral with chemical formula [3] ([4] or [5]). It crystallizes in the hexagonal crystal system typically as small blue hexagonal crystals up to 2 cm length. It has a Mohs hardness of 6.5–7 and a specific gravity of 2.77 to 2.85.

It is hard to distinguish from blue beryl.

Occurs in miarolitic cavities in granite, in alpine veins and in scandium bearing granitic pegmatites. It occurs associated with quartz, orthoclase, muscovite, laumontite, albite, hematite, calcite, chlorite, fluorite, beryl and bavenite.[4]

It was first described from an occurrence in Baveno, Italy. Named after the discoverer, the Italian engineer Alessandro E. Bazzi.[4]

Notes and References

  1. Warr. L.N.. 2021. IMA–CNMNC approved mineral symbols. Mineralogical Magazine. 85. 3 . 291–320. 10.1180/mgm.2021.43 . 2021MinM...85..291W . 235729616 . free.
  2. https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Bazzite Mineralienatlas
  3. http://www.mindat.org/min-586.html Mindat with location data
  4. Web site: Handbook of Mineralogy . 2013-01-07 . 2021-10-19 . https://web.archive.org/web/20211019225654/http://www.handbookofmineralogy.com/pdfs/bazzite.pdf . dead .
  5. http://www.webmineral.com/data/Bazzite.shtml Webmineral data