difference between precious gemstone, semi precious gemstone
difference between precious gemstone, semi precious gemstone
September 30, 2019
The modern GIA grading system doesn’t differentiate precious and semi-precious gems
The traditional distinction between precious and semi-precious stones goes back to the Ancient Greeks. In modern usage the four precious stones are diamond, ruby, sapphire and emerald. Other stones are considered to be semi-precious. The classification reflects the rarity of the respective stones in ancient times as well as their beauty and relative hardness.
Synthetic stones are created or man-made versions of nature’s creations. All of the most important gemstones have been synthesized in labs and some on an industrial scale. Synthetics share nearly all of the same chemical, physical, and crystallographic properties of their natural counterparts but they are man-made and often referred to as “created” gems. Although sometimes difficult to identify, minor variations in trace element chemistry, inclusion patterns, or optical responses allow gemologists to identify them with a high degree of certainty.
Colored glass is simply glass. It can be produced in nearly any color and is popular for its beauty and price. It is frequently referred to as crystal, but it is not crystalline at all and from a gemological perspective, glass is amorphous. Glass is used primarily in costume jewelry. Its distinctive inclusions and optical properties make it an easy identification for gemologists.
Precious and semiprecious gemstones are natural gemstones dug out of the ground; synthetic gemstones are man made gemstones of similar chemical composition to the the natural gemstone Eg Natural ruby verses lab created rubies; originally developed for the laser industry. Coloured glass on the other hand are glasses of any glass composition containing a colouring agent that simulates a gemstone. Eg. Blue glass to simulate Sapphire.
Precious gemstones are usually more expensive than semiprecious stones. Diamond, ruby, emerald, and Sapphire are the stones usually termed precious. Semiprecious stones are mostly the less valuable ones; such as quartz, and nephrite. However some of the rarer semiprecious stones are as valuable as diamond, emerald, sapphire or ruby. Eg. Imperial Jadeite jade, Paraiba Tourmaline, Alexandrite, Demantoid, and others.