potash mines

A potash mine in Rocanville, Saskatchewan. 2007. photographer Troy Fleece for The Canadian Press

What is potash?  The word covers potassium salts, such as potassium chloride, KCl, used in fertiliser.  It was found in Saskatchewan in 1942 while drilling for oil – a massive formation covering most of southern Saskatchewan.  It wasn't successfully mined until the mid 1960s, mostly because there are water layers that make sinking shafts difficult.  The Saskatchewan Mining Association informs us that Sylvite was made Saskatchewan's mineral emblem in 1996, something not obviously part of the living skies campaign.

Potash does well on the market, not that I understand such things, but Saskatchewan is in the throes of a boom the like of which only Alberta and Newfoundland understand.  

Potash is marine in origin, formed by the evaporation of sea water.  In Sask the layer is 1-1.5km below the surface, deposited during the Middle Devonian Prairie Evaporite formation which also extends into Manitoba and North Dakota.  New Brunswick also has a potash industry, of which we hear little, however its capacity is 2 million tonnes; Saskatchewan's is 20 million.  Potash is the third largest mineral product shipped from Canada.

What makes KCl a necessary ingredient in a good fertiliser?  It improves water retention and general yield in food crops.  Because of population growth and the need for more food, more potash is needed, thus the boom, which evidently has abated since 2008 and the global financial crisis.  In 2009 it was $872/tonne, 2011 it was $470.  Saskatchewan, beware.

Stephanie Whitegeology