Gem Type Group Hardness Refractive Index Specific Gravity
Quartz Quartz 7 1.54 2.65

Quartz is one of the most common minerals on earth and although Feldspar makes up more than 50% of the earth's crust, Quartz is by far the most prolific gem material.  Huge quantities of transparent material such as Amethyst, Citrine, Prasiolite and Smokey Quartz are mined every year.  Add to that the huge volume of translucent and opaque Quartz varieties like Agate, Chrysoprase, etc. and you can understand why Quartz is a staple of the gem industry.  Quartz’ excellent hardness and durability also makes it desirable.

 There are Quartz mines all over the globe, with most seeking out the more valuable varieties such as Amethyst.  The material is sorted to separate out the finest material for cutting.  In this process there are tons of reject material that is too included or of undesirable color.  Clean, undesirable color material is often heat treated to create Citrine or Prasiolite. 

The remaining included Quartz is the focus of this article. This included material can be valuable in a number of ways.  The mineral inclusion could be rare in itself, making it a collector's item, though most are only sought after if the inclusions are aesthetically pleasing.  For example, Rutile is a common inclusion in Quartz but is only desirable if there is a moderate amount.  Too much is ugly, not enough is just boring. 

  Just off the top of my head I can think of 10 types of inclusions popular in Quartz, but there's probably twice as many.  The most common are Rutile and Tourmaline. Rutile is the thin often hairlike gold to red needles you see while Tourmaline inclusions tend to be slightly thicker and black. Gold, Silver and Emerald are often found in Quartz and usually mined out of it, but you will see this material in the market as well.  Pyrite and Hematite provide a similar metallic look. Million year old water can be found trapped in Quartz crystals, called Enhydro Quartz.

  Super Seven:

One of the unique included Quartz varieties that has hit the market in the last few years is being coined "Super Seven" touting up to 7 mineral inclusions, including Amethyst, Lepidochrosite, Rutile, Tiger Eye and Cocoxinite.  You can imagine blending that many different varieties of inclusions would make it hard to find good looking sections.  I sorted through thousands of slices to find the pieces that had the most attractive combinations of inclusions. These are fantastic for a show piece pendant with all kinds of necklaces.

  Drusy Quartz:

Another large portion of the Quartz that is unsuitable for faceting yet still has merit is the crystal specimen.  Large perfect crystals with good collector merit are separated and sold.  The rest is sorted for drusy.  Drusy is the cluster of tiny crystals that form a sort of "carpet" of gems.  These can be formed and shaped for use as pendants and other jewelry.  Drusy with good color and/or banding is normally left natural.  The less exciting clear, brown and white drusy is often enhanced with coatings and diffusion.  These coatings and surface diffusion are stable and generally durable as long as you don't chip or grind the surface.  The result is low cost, super bright and vibrant drusies. 

Strawberry Quartzlab Emerald