In our mountains, not all that glitters is gold.
Although precious metals like silver and gold have been mined throughout North Carolina for millenia, the real treasures of our mountains tend to be a bit more transparent. In fact, mines near Mount Mitchell possess the purest quartz crystals known in the world and are used in almost every computer from here to Tibet.
While these quartz deposits make North Carolina a globally important mineral powerhouse for the indefinite future, there is another mineral widely present here that is somewhat easier to find.
Mica can be found almost everywhere in the area, seen glittering on mountain trails, alongside stream beds, and generally any other site that has been dug and disturbed through human development.
Mica is believed to have been mined around here for hundreds, perhaps thousands of years. Native Americans used the lustrous, clear chunks of mica they found as currency and to decorate grave sites, while across the globe India maintained a bustling mica trade focused on using it in local medicines.
Some of the earliest cave paintings discovered also included bits of mica to spice up the artwork. More recently, our area began excavating mica on a large scale in the mid-1800’s, and it has been used in a wide variety of applications since then. Mica is still widely used today, and North Carolina is the mica Mecca of the United States, sourcing over half of the scrap mica in the country.
One of the most defining aspects of mica is its sheet-like nature.
Because of the way individual mica crystals form, they can easily be split into thin, supple plates. Most of the mica in the area was probably formed when Africa collided with our continent more than 200 million years ago, leading to intense pressure and heat deep below the surface. These incredible forces turned clay into sheets of mica.
There is a global market for relatively large, unbroken sheets of mica, which are used in electrical components such as capacitors and as window panes, where mica’s impressive insulation properties and resilience in the face of extreme heat and the elements comes in handy. Edison’s first electric motor in 1878 used mica insulation from North Carolina, for example.
Local mica deposits also greatly aided the war effort during World War II, and Western North Carolina supplied around 75 percent of the mica used in gas masks, armored portholes and the internal components of planes and automobiles at the time.
Mica sheets were heavily mined in the area until the 60s, at which point the cost in both dollars and human lives required to excavate large sheets were deemed too high. Today, most of the sheet mica used worldwide is mined in India. The Blue Ridge mountains are still denuded for mica these days, however it is mostly collected during the mining of other minerals such as feldspar, lithium and silica. The coarsely ground mica that emerges from these operations finds a use as filler for drywall joints, shingles, paints and cosmetics.
Depending on the secondary minerals found in the mica, it can take on a multitude of colors beyond simply clear-white.
As you venture through landscapes in the area, an occasional glance downward is usually all that is needed to pick out a flake or two of this important mineral. Although it tends to be regarded as less lofty than some of the other gems and metals present in and around our mountains, its widespread usefulness and readily apparent beauty make mica one of the true treasures of Western North Carolina.
Don’t take our sparkly soils for granted.
Brannen Basham is a writer and horticulturalist. Together with his wife, Jill Jacobs, he owns Spriggly’s Beescaping. He published his first book, “A Guide to the Wonderful World Around Us: Notes on Nature.” For more information visit www.sprigglys.com.