With no Government money, as Borglum had, Ziolkowski hoped to finance his work by mining the mountain's beryl and feldspar as he went along and selling Indian souvenirs to curious .
The Davidsons claim that their grit is ideal because it contains sparkling particles of feldspar and mica which attract a hungry hen's eye.
But the present cost of processing feldspar is far more than $40 a ton, the gage for fertilizer potassium.
Canadian company still interested in Bovill mine BOISE, Idaho (AP) — A Canadian mining company plans to renew its lease on state endowment land in northern Idaho in hopes of eventually mining clay, quartz and feldspar.
June 19, 2013 - Idaho Press-Tribune