Boomerang Lake, Menangina Station, Menzies Shire, Western Australia, Australiai

Regional Level Types
Boomerang Lake	Lake
Menangina Station	- not defined -
Menzies Shire	Shire
Western Australia	State
Australia	Country

About 6 km SW of Menangina homestead

The sodian potassian hydroxonian meta-autunite was the first reported occurrence of an intermediate member of a predicted (Ross and Evans 1965) solid solution series, with potassium, sodium and hydroxonian end members.The material is unique in two ways. Autunite and meta-autunite are alteration products, however the Boomerang Lake material has precipitated from saline groundwater. The reference was astonished the material could retain its structure and properties of reverse dehydration up to its melting point of 1200 degrees, whereas normally autunite heated to high temperatures cannot.

The discovery was made by Esso Minerals Limited in 1977, from a small area 50 x 100 metres near the northern shore of the salt-pan. It occurs 30-100cm below the surface in saline, gypsiferous red/brown mud as late stage disseminations, infillings of voids and shrinkage cracks up to 1.5mm x 20mm, and occassionally cylindrical root cast and insect burrow channels to 2mm in diameter.

The mineral is bright greenish-yellow, consisting of micaceous crystallites, and fluorescences a strong yellow under both short and long wave ulta-violet light. Small amounts of quartz, gypsum and halite have been found with it. Also an uranium oxide phase as uraninite formed by the reduction of the precipitated autunite phase.

Other Regions, Features and Areas containing this locality

References