Regarding inclusions in gemstones,  in general, it is considered that transparent gemstones should be as clear and free from inclusions as possible.

Inclusions are material that has become trapped in the crystal as it was formed. There are very, very few gems that contain no inclusions at all and there are some, again very few, who contain inclusions that make them incredibly interesting in their own right.

In the short video clip here you see a quartz crystal that has formed with what is known in the gemmology world as a “Three Phase Inclusion” where you find a liquid filled cavity that also contains a gas bubble and a solid. In the video you can see that as the crystal is tilted to the side the gas bubble moves and the solid also moves in turn.

In all gemstones it is inclusions, the quantity and visibility of them, that affects the clarity of the stone.

Clarity is one of the “Four C’s”. For example, a diamond can only be described as internally flawless if it is unmounted so that every part of the cut stone is visible and no inclusions at all are detectable under 10x magnification.

In the vast majority of cases, stones that are seen within the retail environment are already mounted and unless they come with a diamond report they cannot be assessed as being internally flawless.