The world's highest quality quartz deposits are located near the town of Spruce Pine, North Carolina, USA. Situated in the heart of the Appalachian Mountains, the Spruce Pine mining district has been a source of mineral wealth for more than a century. These unique granites were first recognized for their extraordinary sheet mica, which was used as electrical insulation in early vacuum tube electronics. Today, silicon-based semiconductor device manufacturers use Unimin's Spruce Pine quartz in the manufacturing chain. From this unique ore body, Unimin separates feldspar, mica and quartz to yield a quartz concentrate that is used to produce IOTA® quartz, the industry standard for quality and purity.
The alaskites of the Spruce Pine district were created approximately 375 million years ago from magma several miles below the earth's surface. Many magmatic bodies, called plutons, were emplaced in the roots of the Appalachians in the Spruce Pine District around this time, and there they cooled slowly for 100 million years. Today each pluton is slightly different and possesses its own set of characteristic impurities and accessory phases depending on the complex geochemical processes that led to their recrystallization. Unimin's IOTA® ore is recognized by its capacity to produce quartz of exceptional purity, low fluid inclusion content and excellent melting characteristics. Nowhere else in the world have the mineral forming processes yielded an equivalent ore.