Mineralpedia Details for Topaz

Named for an island in the Red Sea that was referred to as Topazios or Topazion, and is called St. John’s Island today. The name of the island itself refers to its difficulty to be found, as Topazion means “to seek” in Greek. The island was not known for the mineral Topaz, however, and any reference to Topaz in ancient texts actually translates to the yellow green olivine variety peridot.  Topaz can befound in veins and cavities within granites, pregmatites, rhyolites and is formed from hot, volatile, hydrothermal fluids. It can also be found in high-grade metamorphic and as a detrital mineral. It can be found in thousands of localities worldwide. Topaz can, albeit rarely, fluoresce under ultraviolet light. Topaz from certain localities must be kept away from sunlight, such as the brown variety from Baldface Mountain, New Hampshire, USA and the sherry-colored crystals from The Cove, Utah, USA, as the color may fade with exposure.

Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/topaz.pdf

Formula

Al₂SiO₄F₂ 

Crystal System

Orthorhombic 

Crystal Habit

Crystalline - Coarse, Prismatic, Massive - Granular 

Cleavage

Perfect, None, None 

Luster

Vitreous (Glassy) 

Color

colorless, pale blue, yellow, yellowish brown, red 

Streak

white 

Class

Orthorhombic - Dipyramidal 

Fracture

Brittle - Uneven 

Hardness

8 

WebMineral

View Topaz 

Mindat

View Topaz 

A nice thumbnail size group of Topaz, with I suspect rutile inclusions since there are thousands of minute, acicular dark red or black crystals surrounding the exterior of the Topaz and on the matrix. The longest Topaz is doubly terminated and 1.7cm.

Hard yellow replacement feldspar by Topaz. It is locally called pyknite and is associated with Fluorite, Quartz, and a green mica.

A complexly crystallized sherry colored Topaz crystal showing many faces. It is a floater.

Sweet little thumbnail with two terminated crystals to 2.5cm.

A colorless, terminated crystal of Topaz with minor Siderite on the termination. Collected by Chris van Laer in 1989.

This is an excellent Topaz crystal group collected by the late Chris van Laer in 1989. It is a group of four colorless crystals with good luster and striations, and each nicely terminated. It was professionally reconstructed by Chris and shows no sign of it.

Sherry colored, slightly striated Topaz crystal with a good termination.

This is a sharp group of Topaz crystals with a light goldish color, clear and all nicely terminated with a little bit of 1-2mm Spessartine crystals. It was collected by Jack Zektzer in 1984 and purchased by Chris van Laer. An excellent specimen.

Prismatic orange "imperial" Topaz crystal, terminated to 2.8cm.

Special Info

Collected by Chris val Laer circa 1979

Waterclear very nice complex crystal of Topaz.

A white, hard, porcellanous mass of Topaz. Comes with a University of Copenhagen tag.

Special Info

Chris van Laer collection

Colorless, striated Topaz crystal with a complex termination.

An outstanding combination and incredibly hard to obtain colorless Topaz with dark smoky Quartz. Both are nicely terminated with no damage. Excellent specimen.

Complex somewhat sherry colored gemmy Topaz crystal.