4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
D : Metal: Oxygen = 1:2 and similar C : With medium-sized cations; sheets of edge-sharing octahedra
ICSD 67673, PDF 15-705, Simpsonite (of Bowley)
is an extremely rare gem that is very attractive in
the bright yellow to yellow-orange colors. It is found
in a few locations worldwide but only available in facetable
crystals from Onça and Paraiba, Brazil and Tabba Tabba,
Western Australia. Gems are usually very small since
crystals are small and clean material is a very small
percentage of the limited supply of Simsonite that has
been found. Most crystals are completely opaque. It
is a very durable gem with hardness of 7.5 and no cleavage.
It would make a very attractive gem for jewelry if it
was more abundant and available in larger sizes.
may exhibit fluorescence under shortwave UV light.
The color of the fluorescence depends on the origin
of the gem; bright blue-white (Western Australia), bright
pale yellow (Bikita, Zimbabwe), medium pale yellow (Ecuador),
light blue (Paraiba, Brazil). If you place your cursor
over the picture above, you will see the light blue
fluorescence of a Simpsonite gem from Paraiba, Brazil.
Simpsonite may also exhibit blue-white
was named in 1938 by Harry Bowley (1882-1958) in honor of Edward Sydney Simpson (1875-1939), government mineralogist and
chemist of the Geological Survey of Western Australia. The Simpson
Desert in Northern Territory, South Australia and Queensland in central Australia
was also named for him. In 1897 he became mineralogist and assayer with the Geological Survey of Western Australia. He helped to establish the Western Australian School of Mines.
Simpson was a founder of the Natural History and Science Society of Western Australia and its successor, the Royal Society of Western Australia which awarded him the Kelvin Medal in 1929. He was awarded the Clarke Medal by the Royal Society of New South Wales in 1934.
Simpson published A Key to Mineral Groups, Species and Varieties in 1932 and a three-volume set Minerals of Western Australia was published after his death
in 1939. Harry Bowley was appointed to succeed Simpson
as Government Analyst in 1939. Bowley joined the Western Australian Geological Survey
Laboratories in 1897, rising to become Director of the Western
Australian Government Chemical Laboratories in 1946.
distribution: from Tabba Tabba, Western Australia. At
the Alto do Giz pegmatite, near Parelhas, and the Onça
mine, about 25 km distant, Rio Grande do Norte, Brazil.
In the Al Hayat and Mdara mines, Bikita, and at the
Benson No. 3 pegmatite, Mtoko, Zimbabwe. In Congo (Zaire),
from Mumba, near Lake Kivu, Kivu Province, and in the
Manono pegmatite, Katanga (Shaba) Province. At the Leshaia
pegmatite, Vuoriyarvi carbonatite complex, Kola Peninsula,
Russia. In Canada, from the Tanco pegmatite, Bernic
gems for sale:
x 2.70 x 1.39 mm
(but we have others)
are of the actual gem offered for
sale. Gem images are magnified to
rare gem is from Brazil.
It is very slightly included. It is very bright