Gemstone Inclusions. The good, the bad, and the amazing.

What are gemstone inclusions?

Inclusions within gemstones can be described as any material that is trapped within a mineral at any point of the mineral’s formation. Inclusions can range from gas filled bubbles to insects to fractures and much more. There are so many different types of inclusions that the list is essentially endless, as scientists are constantly discovering new varieties of gemstone inclusions.

Are inclusions always a bad thing?

Gemstone inclusions are often regarded as a negative thing, however this is not always the case. Whilst inclusions in diamonds are generally viewed as a disadvantage, the same cannot be said for coloured gemstones.
Inclusions act as a marker of a gemstone’s unique identity, much like a finger print does for people. Each gemstone is totally unique and inclusions can tell researchers about many of the properties of each stone. Gemmologists use inclusions to help uncover if a gemstone is organic or synthetic or even to uncover where the gemstone was geographically formed.

amber fossil

In some instances inclusions can add to the value and beauty of a gemstone. For example, insects found within amber can be highly sought after. Other positive inclusions include those caused by rutile needles which can create the formation of ‘the star effect’ or chatoyancy ‘cat’s eye’ in some coloured gemstones. A star ruby or sapphire has what looks like six rays of light emitting from a central point, like a glowing star. These inclusions can certainly make a gemstone more precious, valuable and sought after.

star sapphire


A wispy horse tail like inclusions sometimes found in demantoid garnet is another example of a positive inclusion. This inclusion also often indicates the stone as having Russian origin.

demantoid garnet inclusion

Inclusions in gemstones covers an array of different things and it is important to note that the term is ‘inclusions’ not flaws or defects. Whilst diamonds with fewer inclusions are considered better, for coloured gemstones inclusions are not always a bad thing and in fact sometimes they can add value and beauty to a stone. Inclusions in gemstones are just another example of the complexity and uniqueness of every gemstone.