Microcline is a member of the Feldspar group of minerals and is an important igneous rock-forming mineral, common in Granite and Pegmatites. It is also associated with, and hosts, numerous high-quality minerals including Smoky Quartz, Quartz, Spessartine, Fluorite, Schorl and Aquamarine. Its varied colors include white, grey, greyish yellow, yellow, tan, salmon-pink and blue-green (Amazonite is the blue-green variety of Microcline) and displays a vitreous luster.
The crystal system for Microcline is triclinic. Crystals are prismatic, elongated and often large. Like enormous large; arguably the largest of any species, to 50 meters and 13,500 tons! Other forms include grainy, massive, compact crystal aggregates and twinning.
This particular mineral is abundantly common and found worldwide, but exceptional specimens are found in fewer localities including Argentina, Canada, Italy, Malawi, Namibia, Pakistan and the USA (Pennsylvania).