| From the Ground Up: Stone Classification & Grading
Do you ever wonder about the stones you find out in the world? Whether from an heirloom piece of jewelry or something you find in your backyard, here is a nice rundown on how stones are generally classified.
Gemstone: Any stone that’s used to make jewelry and other adornments. You can plunk a random landscaping rock into wire to form a ring and BOOM it’s now *technically* a gemstone. I don’t recommend selling random garden rocks as gemstones. It falls into a murky area of exploiting already misunderstood terms. As a working, ethical, definition, we’ll say that gemstones are any minerals or other stones commonly used in the making of jewelry. The $5 strand of Fossil Coral is gemstone and the $3000 strand of diamonds is gemstone.
Precious Gemstone: This has historically referred to Diamond, Sapphire, Ruby and Emerald. The classification is starting to fall out of favor. It’s considered inaccurate as it doesn’t account for all factors that contribute to the cost of a natural stone. For example, diamonds are quite abundant, but tightly controlled by cartels like DeBeers to keep the prices high. In addition, industrial-grade diamonds are inexpensive enough to be used on common tools. Lower quality Sapphire, Ruby, or Emerald can also carry a lower price tag than fine specimens of semi-precious stones like Garnet or Amethyst.
Synthetic Gemstone: This is a really important thing to understand. Some commonly accepted “stones” are synthetic. Goldstone and Cherry Quartz are both synthetic. They do NOT occur in nature. It’s pretty common knowledge that other types of naturally occurring stones can also be artificially created in labs. For example, all Cubic Zirconia is lab-created. (Note: Don’t confuse Cubic Zirconia with Zircon. Zircon actually comes out of the ground.) Composite Gemstone: These stones have pieces of gemstone in them, but are not entirely made of stone. Generally, these are made from a combination of stone fragments and resin. The stone fragments and/or the resin may also be dyed. Any type of Impression Jasper or Serpentine with Bronzite are good examples of composite gemstones.
An important note on grading: There isn’t a universal system for grading gemstones. The GIA has a commonly accepted method for grading diamonds. Only a gemologist certified by the GIA for grading diamonds is qualified to assign a GIA grade. In all other stone types, terms like “A-Grade”, “AAA-Grade”, or “B/C Grade”, are SUBJECTIVE terms used by the seller. One vendor’s AAA-grade Amethyst may look like another’s B-Grade. Other vendors may have no grading system at all, and the price tag will tell the story. I like to take a “what do I like?” approach. Sometimes that saves me money because I honestly prefer some inclusions. Other times, it means that I pay an embarrassing amount for “practically perfect.”
- Erin G.
Lex Date 7/29/2019
Thanks so much for this! I'm always trying to better understand the materials I use, and I love learning about gemstones.
Kristy Le Date 7/29/2019
Awesome info and read! Thank you!
Susan Graham Date 7/29/2019
What source do you recommend for identifying different semi-precious stones?
Sharon Redgrave Date 7/30/2019
Great information and very useful. Thanks!
Lisa Bryant Date 7/30/2019
Thanks Erin. This was good information. I didn't realize, but should have known, the impression jaspers and cherry quartz were actually composits and only 4 stones are technically considered "precious" stones! Who knew!