The Basics of Understanding Gemstones (Part 1)

The Definition of “Gemmology”.

noun: gemology
  1. the study of precious stones.

Our Mission…

The Gem Museum’s mission is to help people appreciate the value of gems through understanding quality and learning about authenticity. Therefore in this two part series, we would like to introduce to you 6 categories of gems and gem materials.

1) Crystal Systems

First of all, here is a need to first understand crystals, in order to understand the structural and optical properties of gemstones. It is from here that you can identify the gemstones. Most miners, for example, in Thailand, Sri Lanka or Myanmar, they do not have formal education. They grow up in mines and start mining for gems at a very young age. However, they could probably identify the rough gem materials, simply based on their observations of structural and optical properties of gems.

gemstone crystals
An overview of the 7 Crystal systems
cubic system
Examples of cubic system: Diamond, spinel, garnet, fluorite
Aquamarine is in the Hexagonal crystal system.

2) Organic Gem Materials

Most people do not realise that these are considered gems too. One of the classification of gem materials is ‘organic’ gems. Organic gems mean that the gem materials was formed through process involving life organisms and some examples are amber, pearls, and even petrified wood.

Fossilized Coral

3) Phenomenal Gems

Finally, in this post, we will talk about some gemstones with special optical effects. Phenomenal Gems have very unusual optical properties. Not all gem materials exhibit optical phenomenal. The optical phenomenal of a gem material could be due to internal reflection of the inclusions, such as cat’s-eye. Another possibility is the structural arrangement of the material, such as moonstones that give the moonlight sheen, described as “Adularescence”. Most of all, our gem museum has a unique collection of double stars and we are still in the midst of searching for more double stars too!

star sapphire
A star sapphire set in a ring.
Labradorite exhibits an optical effect that is due to interference caused by the layering of the material.

In conclusion, there are many ways to categorise and classify gem materials. Hence, look out for the next part of this blog, so that you can understand more about gems and gemstone materials!