Datolite

[McomeMeteorite]

Datolite

Chemistry: CaBSiO4(OH), Calcium Boron Silicate Hydroxide.
Class: Silicates
Subclass: Nesosilicates
Group: Datolite
Uses: As a mineral specimen, rarely as an ornamental stone and as a minor gemstone.

Color is white, colorless, yellowish, reddish, gray, brown and green.
Luster is vitreous to greasy.
Transparency: Crystals are transparent to translucent.
Crystal System: Monoclinic; 2/m
Crystal Habits include short prismatic to wedge shaped tabular crystals with complex and richly faceted terminations. Also in porcelain-like masses that form nodules. Aggregates can be fibrous or granular.
Cleavage is absent.
Fracture is conchoidal to uneven.
Hardness is 5 - 5.5
Specific Gravity is 2.8 - 3.0
Streak is white.
Associated Minerals are prehnite, danburite, babingtonite, epidote, copper, calcite, quartz and zeolites.
Notable Occurances include Russia; Lake Superior region of Michigan and Paterson, New Jersey, USA; Bancroft, Ontario, Canada; Charcas, Mexico; Schwarzwald, Germany and Norway.
Best Field Indicators are crystal habit, absence of cleavage, hardness and color.

Datolite - Dalnegorisk, Russia


17,5 KB

(C) Chinellato Matteo cubo = 1 cm.

[amaltheus]

Here we are again! Report written in english

Leggo come aree di provenienza:

??Russia; Lake Superior region of Michigan and Paterson, New Jersey, USA; Bancroft, Ontario, Canada; Charcas, Mexico; Schwarzwald, Germany and Norway??

Uno pu? pensare: e da noi? Non si trova?

Eppure sono famosissime (e apprezzate anche all?estero) le datoliti delle formazioni ofiolitiche dell?Appennino Settentrionale: una fra tutte l?area di Cerezzola, con cristalli incolori lucentissimi e brillantissimi nei basalti.

Nessuno ha foto di campioni locali?


marco