The Chinese red feldspar controversy: chronology of research up until July 2009
Red copper-containing plagioclase feldspar from Oregon has been available for over a century. In the early 2000s, new localities for copper-bearing feldspar were reported from the Democratic Republic of the Congo and from Tibet or an unspecified locality in China.
Sunstone Labradorite from the Ponderosa Mine, Oregon
The Ponderosa mine is now producing commercial quantities of the gem-quality labradorite feldspar known as sunstone.