Northupite, Trona, (Borax Lake, California, USA); Bradleyite,
Gaylussite, Northupite, Shortite, Trona (John Hay, Jr.
Well No. 1, Wyoming, USA).
Pirssonite is named after American geologist Louis Valentine Pirsson.
Pirssonite is one of several carbonate minerals that form in non-marine
evaporite deposits. Other evaporite carbonates include trona, gaylussite, northupite, nahcolite and thermonatrite. Evaporite
minerals are geologically important because they clearly are related to the
environmental conditions that existed at the time of their deposition, namely
arid. They also can be easily recrystallized in laboratories in order to confirm
their specific characteristics of formation.
include the type locality at Searles Lake, San Bernardino County, California as
well as Deep Spring Lake, Inyo County and Borax Lake, Lake County, California,
USA; Mont Saint-Hilaire,
Quebec, Canada and elsewhere.
Pirssonite and gaylussite, Na2Ca(CO
3)2 - 5H2O, differ only in the
number of water molecules, yet their symmetries are quite different. This is an
indication of a change in their respective crystal structures. The two are best
distinguished by their crystal habits in which pirssonite has a distinctive
tabular diamond-shaped crystal form. Pirssonite can lose its water molecules and
specimens should be stored in a sealed container.
the USA, in California, from Searles Lake, San Bernardino
Co., at Borax Lake, Lake Co., in Deep Spring Lake, Inyo
Co., and at Owens Lake, Mono Co.; in the John Hay, Jr.
Well No. 1, about 30 km west of Green River, Sweetwater
Co., Wyoming. On the Arizaro, Pastos Grandes, and Pozuelos
playas, Salta Province, Argentina. From the Jequetepeque
River Valley, northwest Peru. On the Otjiwalundo Salt
Pan, about 400 km west-northwest of Otavi, Namibia.
In the Beypazari Basin, Ankara, Turkey. On Mt. Kukisvumchorr,
Khibiny massif, and Mt. Alluaiv, Lovozero massif, Kola