Gem Natural Stone
Why many gem collectors prefer natural gem stones
If you look at a gem, you may see it labeled as a natural gem stone.
You may ask yourself, "What, then, is an unnatural stone?"
For a gem to be called natural, the following statements must be true:
- The stone must have formed completely without human intervention. In other words, it is found in the Earth as is. Nothing was done during the formation process to enhance or 'culture' the stone.
- After it is mined, a natural gem stone cannot undergo any special processing that changes the composition, color or structure of the stone. This includes heat treatment or any chemical treatment other than cleaning or polishing compounds.
Certain 'after mining' procedures which enhance the natural appearance are allowed. These include:
- Cutting: This is shaping the crystal by breaking off pieces along natural lines of cleavage.
- Polishing: This can apply to cut crystalline stones as well as to the amorphous stones, such as turquoise.
- Shaping: Depending on the composition of the natural gem stone, it may lend it self to being shaped.
- Scribing, engraving, or other surface decorations.
Anything else is labeled as synthetic gem stones, enhanced or cultured.
Anyone who has seen a collection of loose gem stones in their natural state can appreciate the need for polishing and cutting. However, the end result is to highlight the existing appearance, not to alter it.
Why is a gem that is a so called gem stone natural preferred over the synthetic gem stone version?
Since we cannot control or initiate the formation of natural gem stones, they must be found. This puts a real limit on the quantity of natural gems that are available.
Natural gem stones are often marked by the impurities, whether chemical or structural, that occur during their haphazard formation. The gem purist will argue that these impurities which give the natural gem stones their character and charm.
Here are several of the better known gem stones and how they are formed in nature:
The hardest material found in nature.
The diamond literally sets the bar for hardness. Most hardness scales use the diamond to define their upper limits.
Being composed of pure carbon makes the diamond gem stone unique in another respect.
It is one of the few gem stones, natural or synthetic, to be made from a single element. The natural diamond gem stone is formed in the earth by the application of tremendous heat and pressure on carbon deposits over a long period of time.
Made up primarily of aluminum oxide (also known as corundum), this gem in its natural state is usually a bluish stone and the corn flower blue sapphire gem stone that comes from Sri Lanka or Ceylon considered the best natural gem stone in the world.
However, Sapphires can come in a range of colors including pink, orange, yellow or green. The color range is caused by chemical impurities in the stone.
A close cousin to the sapphire, it is also based on the compound aluminum oxide. The natural gem stone ruby gets its reddish hue from traces of the metallic element chromium in the chemical mix.
All of these gems are found as natural stones and are mined throughout the world. As loose natural stones, they may resemble a collection of shiny pebbles.
However, to the experienced gemologist or collector, each gem has a natural potential for beauty that makes it a cut above the common stone.