Pictorial Gemstone Guide

3 Types of Gemstones
Natural ~ Synthetic ~ Imitation

Natural Gemstones

 Natural uncut emerald and amethyst crystals.  The many inclusions (sometimes called flaws) inside the emerald are common and accepted but not so much within an amethyst.  Notice the colorless areas inside the amethyst.  The gem cutter may grind these areas away along with any very visible inclusions within the stone.  The finished cut gem may have only 20% the weight of the original rough material.


"Watermelon" Tourmaline Crystal

  Natural is easy to understand.  Rare geological occurrences allow gem materials to develop with no assistance from man.  Only a small percentage of gem material found is of high enough quality for jewelry use.  If a specimen lacks the clarity or color to be fashioned into a gemstone it may still be enjoyed as a fascinating mineral specimen.  Here are a few from our state of North Carolina:

 
from left:
Emerald crystals from the Crabtree mine in Spruce Pine, NC.
Ruby crystals from Lincoln County NC.
Aquamarine specimen from Spruce Pine NC.

Synthetic Gemstones

 
on left:
Synthetic diamond in the rough form and after faceting ~ made using a high pressure, high temperature process that dissolves carbon at high temperatures.
on right:
Synthetic sapphire rough after creation in 5 different colors, split in two to relieve stress within the crystals

Makers of synthetic gemstones dislike describing their gems as "synthetic" since this term is sometimes used in conversation to mean "fake".  This is a shame since synthesizing a gemstone is no small accomplishment.  A true synthetic has the same chemical composition and crystal properties as it's natural counterpart.  These are the two things that define what a gemstone is.  A synthetic could be described as "real" or "genuine" but these terms are too vague and make no distinction between synthetic vs natural gems, which have a huge difference in value.

   
Beautiful true synthetics.  Man made sapphire, ruby and emerald.  All gemological instruments will indicate that these gems are in fact sapphire, ruby and emerald.  It takes a skilled gemologist to find trace indications of a natural or synthetic origin.

  Synthetic is the correct gemological description for these gems, but they are rarely sold that way.  The federal trade commission has allowed terms such as created gemstones or cultured pearls to be used.  These terms can cause confusion.  Sometimes the confusion is intentional when ordinary synthetics such as cubic zirconias are sold under fanciful names such as "diamonesse".  The processes used to make most synthetic gems are fairly inexpensive.  This makes synthetics an affordable, beautiful and durable alternative to natural gems.

Imitation Gems

 

An imitation gem can be made of anything.  Better imitations are often true synthetics of a different gem, sapphire for example, that has been color altered to imitate other gems.  These better imitations have the same excellent hardness that natural sapphire has.  Imitations can also be mere glass which looks good if it is well cut but is soft and will soon become abraded when worn.  Some natural gem materials are altered to imitate other gems.  Above is a red and green example of quartz, altered to imitate emerald and ruby.  You can see the lines of dye running through the cracks created from quenching hot gems in a cold dyed liquid.