Roger Weller, geology instructor
[email protected]
copyright 2006-R.Weller
Mineral
Information on:
topaz
Chemical Group:
silicate
Chemical Formula: [Al(F,OH)2]AlSiO4
Color: colorless, white, pale blue,
yellow, yellow-brown, brown, pink
Streak: white
Luster: vitreous
Hardness: 8
Specific Gravity: 3.5 to 3.6
Cleavage: 1 direction, perfect, perpendicular to the length of the crystal
Crystal Forms and Habits:
Orthorhombic system
Topaz forms prismatic crystals
Mineral Associations: found in pegmatites
Identifying Characteristics: Cleavage surfaces of topaz are very flat and
smooth.
Uses: a gemstone
Occurrences: Brazil, Mexico
Toxicity: when-swallowed- low
when inhaled- high
Additional Information: