Quartz has been a precious player in the evolution of humankind. Fashioned into knives, tools, and adornments, it was essential to the survival of early man. Since then, the Romans carved it into seals, and the Victorians created an endless array of cameos and intaglios.

Today, quartz remains one of the most popular gemstones in the world. Loved by gem aficionados and metaphysical experts, quartz’s many personalities deliver one stunning surprise after another.


Since quartz is a vital part of the earth’s crust, it can be found in nearly every corner of the globe. Every continent, and all 50 States produce some variety of quartz.


Quartz is commonly separated into two groups based on the type of crystallization. First, the macrocrystalline, whose crystalline formations can be observed with the naked eye. Second, the microcrystalline, whose individual quartz crystals are too small to be easily distinguishable under a regular microscope. Both are used in fine jewelry.

Among the common macrocrystalline quartz varieties are amethyst, ametrine, citrine, smoky, prase, rose, and in its purest form, clear colorless quartz called rock crystal.

Most microcrystalline quartzes are grouped under the name “chalcedony.” Common incarnations include black onyx, carnelian, sard, chrysoprase, and bloodstone. Other varieties such as moss agate, jasper, and petrified wood are common in designer pieces.

Several types of quartz are distinguished by their unusual inclusions. Rutilated quartz – a clear macro quartz with golden needles of another mineral called rutile – provides unparalleled individuality, as does moss agate – a milky micro quartz with tree- or plant-like inclusions.


Quartz gems are cut and carved in all varieties of shapes and sizes for jewelry. Crystal quartz varieties, including citrine, prase and ametrine, are popular for designer lines. Since large sizes and well-matched crystals are readily available, designers can create a grandiose appearance at reasonable prices.

Individual designers look for unusual specimens of quartz gems to create fantastic pieces. Because large rough is available and relatively inexpensive, talented lapidaries experiment with all sorts of alternative cutting methods.

Amethyst is the most precious of the quartz species, but is still very affordable. Because quartz is so abundant – particularly the alternative varieties – it is accessible to everyone’s budget. Its versatility offers a look for every price point and style.


Certain varieties of crystalline quartz have long been subjected to heat treatments to enhance or change the stone’s color. For example, delicately heat-treating light colored amethyst or smoky quartz can turn the stone an attractive golden yellow color. Additionally, when heat treated, other amethyst will turn into the gentle green color known as prasiolite. Since heat treatment is such a common and widely accepted practice, it has virtually no effect on a stone’s price.

Quartz was also one of the first gems to be synthetically grown on a large scale, precipitated by its use in crystal radios in the 1940s. To this day, the computer industry relies heavily on synthetic quartz.


All varieties of quartz are very easy to care for, and typically demand little attention. To clean quartz jewelry at home, let the piece soak overnight in a solution of warm water and a gentle dish detergent. In the morning, use a soft brush to clean the stone and around the setting, and its luster will return immediately. Quartz should be cleaned often to avoid the buildup of cosmetics and dirt, which can affect the stone’s brilliance.


Family: Quartz
Chemistry: SiO2
Refractive Index: 1.544 – 1.553
Birefringence: .000 – .009
Specific Gravity: 2.65
Hardness: 7 (Moh’s Scale)
Color: All visible colors