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Posted by Rock Currier  
avatar Mirabilite
September 06, 2009 01:45AM
Click here to view Best Minerals M and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities? After each set of pictures there should be some descriptive text. If none appears it means that we need someone to tell us about the specimens from that locality and something about the geology of the occurrence.

Na2SO4·10H2O monoclinic

Mirabilite, Soda Lake, Carrizo Plain, San Luis Obispo Co., California, USA©

Mirabilite is a water soluble evaporate mineral that forms in many salt lakes, often on a seasonal basis when the temperature and salt content of the brine is favorable to its formation. It is not a stable mineral under normal conditions and when removed from the brine will under most conditions quickly begin to loose its water and a crust of sodium carbonate (Thenardite) will start forming on its surface. If you quickly placed the specimens in an ice chest at about 0 degrees you could preserve this mineral intact. In the space of an hour or so the nice specimens you have collected will be just a pile of white Thenardite fragments.

California, San Luis Obispo Co., Carrizo Plain, Soda Lake



Mirabilite can be sometimes found at this locality when conditions are favorable for its growth in the mud just below the salt crust of this sometime dry lake. Collecting there is one of the dirtiest collecting experiences that field collectors will likely ever encounter. Use this link if you would like to read about collecting Mirabilite, Thenardite and other minerals at Soda Lake.
[Rock Currier 2009]

Click here to view Best Minerals M and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Rock Currier
Crystals not pistols.

Edited 3 time(s). Last edit at 07/26/2010 09:37AM by Rock Currier.


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