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Large Brown Smoky Quartz
HEXAGONAL

Smoky Quartz

SiO2

Hardness
7
Refractive Index
1.54–1.55
Spec. Gravity
2.63–2.65
System
Hexagonal
Smoky Quartz is the brown "smoky" variety of Quartz. It ranges in color from light grayish-brown to deep black. Smoky Quartz can be opaque, but is almost always transparent to translucent, even when in its darkest color shade. Smoky Quartz is very common and was never an historically important gemstone. Only in very recent times has it become a popular gemstone.

About

Smoky Quartz is an affordable gemstone, and it has become popular in jewelry. Since it is very common and often lacking flaws, small Smoky Quartz gemstones are rarely encountered. In fact, gemstones can reach several hundred carats with minimal flaws. The color of Smoky Quartz is thought to be caused by natural irradiation of Quartz. Citrine, the yellow to orange variety of Quartz, sometimes has a brownish tinge, and a stone can thus be borderlined between Citrine and Smoky Quartz.

Uses

Smoky Quartz is an important brown gemstone, and is used in various form of jewelry. It is especially used as ring and pendant centerpieces. Lesser quality stones, often with lighter color, are cut as cabochons or tumbled into beads. Large spheres and carvings are also cut from Smoky Quartz.

Varieties

✓ common  · ✗ uncommon

Treatments & Enhancements

Most Smoky Quartz is naturally colored, though some of the darker colored forms are colored by exposing clear Quartz to irradiation through gamma rays.

Sources

Smoky Quartz is found throughout the world. Important deposits exist in Brazil, Madagascar, Mozambique, Australia, Switzerland, Scotland, and the United States (Colorado and New Hampshire).

Similar Gemstones

Few gemstones are confused with Smoky Quartz, though brown Topaz can be the same color but is harder, and brown Diamonds have more fire and are much harder. Smoky Quartz may also resemble other black gemstones such as Schorl Tourmaline and Melanite Garnet, but these gemstones are always opaque, whereas Smoky Quartz is usually at least translucent.

Further Reading

Faceted

See all 9 faceted photos →

In the Rough

Jewelry