Accessibility options

Switch to preferred accessibility theme:


Increase or decrease the text size:

  • Internet Explorer: View > Text Size > Largest

Keyboard navigation and access keys:

  • A - Accessibility options
  • 0 - Skip navigation
  • 1 - Home
  • 2 - Alexandrite chapters
  • 3 - Alexandrite directory
  • 4 - Alexandrite forums
  • 5 - Alexandrite gemstones
  • 6 - Alexandrite localities
  • 7 - Contact information
  • 8 - About Alexandrite Guide
  • 9 - Sitemap
  • Press ALT + Access Key, then ENTER.

Close

Alexandrite

Tsarstone collectors guide

Australian alexandrite

One of only four recorded occurrences of alexandrite in Australia occurs near Dowerin, Western Australia. Known since 1930, the deposit was the first recorded in Australia and has yielded many small alexandrite crystals. Recent re-working of the deposit has allowed further examination of the gem-bearing rocks.

Locality details
CountryAustralia
RegionWestern Australia
ProvinceMidlands
LocalityDowerin
Latitude-31.2000
Longitude117.0333
Altitude990
Time zoneUTC+8
Locality maps
MapSatellite
Map of Dowerin Satellite of Dorwin

A deposit of chrysoberyl, including the variety alexandrite, occurs near Dowerin, in the southwestern region of the Archaean Yilgarn Craton, Western Australia. The deposit is situated in the northern part of the Lake Grace Terrain, a crystal component of the southwestern Yilgarn Craton, in granulite-facies gneisses adjacent to the margin of the Kellerberrin Batholith.

Beryllium mineralization at Dowerin occurs in plagioclasequartz-biotite-garnet gneiss and cross-cutting tourmaline-plagioclase veins situated adjacent to lenses of actinolite-cummingtonite-phlogopite schist. Crystals of chrysoberyl are found embedded in almandine or plagioclase, and closely intergrown with biotite and/or zincian hercynite in the host-rock gneiss. Minor Cr and Fe in the alexandrite variety of chrysoberyl were possibly derived from associated zincian hercynite and/or almandine. Trace beryl occurs as anhedral interstital grains between crystals of chrysoberyl, plagioclase and biotite, and as rare inclusions in chrysoberyl.

Textural and mineral chemical evidence suggests that chrysoberyl and zincian spinels formed during granulite-facies regional metamorphism and probably pre-dated the formation of metamorphic tourmaline-plagioclase veins during the same metamorphic episode. The Be, B and Zn required to form chrysoberyl, beryl, tourmaline and zincian spinels may have been released by metamorphic reactions in host-rock metapelites during prograde granulite-facies metamorphism.


Page 1 of 20 Back to Top >>
1 2 3 4 5 6 7 8 9 10 ... Last
Bibliographic details
Page title Australian alexandrite, Dowerin
Author David Weinberg
Website title Alexandrite Tsarstone Collectors Guide
Date published 03 July 2010 06:11 UTC
Date accessed 19 April 2014 01:25 UTC
Permanent link http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002
AMA style
David Weinberg. "Australian alexandrite, Dowerin". In Alexandrite Tsarstone Collectors Guide. July 03, 2010, 06:11 UTC. Available at: http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002. Accessed April 19, 2014.
APA style
"Australian alexandrite, Dowerin". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 01:25, April 19, 2014, from http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002.
Bluebook style
"Australian alexandrite, Dowerin", http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002 (last visited April 19, 2014).
Bluebook: Harvard JOLT style
See Alexandrite Tsarstone Collectors Guide, "Australian alexandrite, Dowerin", http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002 (Information about Australian alexandrite findings and mining in Dowerin, Australia.) (as of Apr. 19, 2014, 01:25 GMT).
CBE/CSE style
David Weinberg. "Australian alexandrite, Dowerin". In Alexandrite Tsarstone Collectors Guide. 2010 Jul 03, 06:11 UTC.[Internet], Alexandrite Tsarstone Collectors Guide; 2010 Jul 03, 06:11 UTC [cited 2014 Apr 19]. Available from: http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002.
Chicago style
David Weinberg, "Australian alexandrite, Dowerin", http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002, (accessed April 19, 2014).
MLA style
"Australian alexandrite, Dowerin". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 06:11 UTC. 19 Apr 2014 http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002
MHRA style
David Weinberg, "Australian alexandrite, Dowerin", Alexandrite Tsarstone Collectors Guide, 03 July 2010, 06:11 UTC, http://www.alexandrite.net/viewpage.html?id=ALXS-001-00002 [accessed 19 April 2014].
Close options details