Name/Title
Topaz / Clevelandite / QuartzEntry/Object ID
2004.1.110Description
Chemical Composition: Al 2 SiO 4 (F, OH) 3
Crystal System: Orthorhombic System
Description: Common Name: Topaz / Clevelandite (Albite)
Group Name: Silicates
Chemistry: Al 2 SiO 4 (F, OH) 3 / CaAl2Si2O8 / SiO2
Location: Ghundao Hill, Pakistan
Description: White base with gray layered blobs and light pink/brown crystals.
PHYSICAL CHARACTERISTICS:
Color is clear, yellow, orange, red, blue and green.
Luster is adamantine to vitreous.
Transparency crystals are transparent to translucent.
Crystal System is orthorhombic; 2/m 2/m 2/m
Crystal Habits include a prismatic crystal with usually two different prisms that produce a rounded or sharp diamond-shaped cross-section. The termination is typically capped by a dome forming a roof like top. Another dome can modify the termination producing a point at the juncture of the two domes. A basal pinacoid can flatten the prisms termination or truncate the top of the domes. The pinacoid, multiple domes and occasionally orthorhombic pyramid faces can produce a complex, multifaceted and well formed termination. Topaz can be granular and massive.
Cleavage is perfect in one direction, basal.
Fracture is conchoidal.
Hardness is 8.
Specific Gravity is approximately 3.4 - 3.5+ (above average)
Streak is white.
Associated Minerals include quartz, tourmalines, micas, brookite, cassiterite and fluorite.
Other Characteristics: index of refraction is 1.61 - 1.64. Prism faces maybe striated lengthwise.
Best Field Indicators are crystal habit, color, density and hardness.
Fracture: conchoidal
Hardness: 8 Topaz
Luster: Vitreous
Occurrence: Topaz is commonly associated with silicic igneous rocks of the granite and rhyolite type. It typically crystallizes in granitic pegmatites or in vapor cavities in rhyolite lava flows like those at Topaz Mountain in western Utah. It can be found with fluorite and cassiterite in varios areas including Ural and Ilmen mountains of Russia, in Afghanistan, Sri Lanka, Czech Republic, Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil, Mexico, Flinders Island and the United States.
Some clear topaz crystals from Brazilian pegmatites can reach boulder size and weigh hundreds of pounds. Crystals of this size may be seen in museum collections. The Topaz of Aurungzebe, observed by Jean Baptiste Tavernier measured 157.75 carats.[10]
Colorless and light-blue varieties of topaz are found in Precambrian granite in Mason County, Texas[11] within the Llano Uplift. There is no commercial mining of topaz in that area.
Notable Occurrences include Minas Gerias, Brazil; Pakistan; San Diego Co, California; Ural Mountains, Russia; Mexico and the Thomas Range, Utah.
Rock Type: Sedimentary
Specific Gravity: 3.4-3.5
Streak: white
Variety: Pure topaz is colorless and transparent but is usually tinted by impurities; typical topaz is wine, straw yellow, pale gray or reddish-orange. It can also be made white, pale green, blue, gold, pink (rare), reddish-yellow or opaque to transparent/translucent.
Orange topaz, also known as precious topaz, is the traditional November birthstone, the symbol of friendship, and the state gemstone for the US State of Utah. [5]
Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Brazilian Imperial Topaz can often have a beautiful bright yellow to deep golden brown hue, sometimes even violet. Many brown or pale topazes are treated to make them bright yellow, gold, pink or violet colored. This variety is the most sought-after and highly valued among the topaz gems. Some imperial topaz stones can fade on exposure to sunlight for an extended period of time. [6][7]
Blue topaz is the Texas state gemstone.[8] Naturally occurring Blue Topaz is quite rare. Typically, colorless, gray or pale yellow and blue material is heat treated and irradiated in order to produce a more desired darker blue.[7]
Mystic topaz is colorless topaz which has been artificially coated giving it the desired rainbow effectCollection
Suomynona Mineral Collection, Suomynona CollectionAcquisition
Accession
2004.1Source or Donor
Suomynona Mineral CollectionAcquisition Method
DonationDimensions
Height
4-1/2 inWidth
8 inLength
11-1/4 inWeight
11.16 ozDimension Notes
Dimension taken at widest pointsLocation
Location
Display Case
FS-6Room
Frieda Smith HallBuilding
Crater Rock MuseumDate
January 3, 2024Location
Container
Center / FrontDrawer
BottomShelf
Right, RightWall
EastBuilding
Freida Smith HallCategory
PermanentMoved By
Steve MillerDate
October 23, 2012Location
Drawer
CenterShelf
Bottom South, Bottom SouthWall
North 2nd centerHallway
Discovery HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Scott LonganDate
August 26, 2009Location
Container
Center / FrontDrawer
BottomShelf
RightCabinet
Case# 63Wall
EastRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
Permanent
