Inside diamond 1/2

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What is hidden inside a diamond? 1/2

Just like snowflakes, every single diamond is different from each other, even if at first glance it may not seem that way. One of the aspects that most makes a mineral unique – and in particular the diamond – is purity.

Pyrope red crystal, a type of garnet that is generally found in highly included diamonds.
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The small inclusions that characterize each individual gemstone, different from each other in shape, color, size and orientation in space, are called ‘characteristics of purity’. Each mineral species has its own series of inclusions that tend to repeat themselves and that often allow gemologist analysts to distinguish one mineral from another: for example, the garden effect is characteristic of emerald and no other gem in the world besides him can present this type of inclusion. In the case of the diamond there are some characteristics of purity that are easier to trace and visible if you look at the stone under a 10-magnification loupe: we are talking about feathers, small fractures that take on a whitish color and appear more or less linear, or pin points, tiny crystals that are so small that they cannot be assimilated to anything but small whitish dots; if very numerous and grouped they create nebulous areas that will be called clouds.

Spectacular four-pointed star-shaped cloud made up of countless pin points.
Photo credits: John I. Koivula/GIA –

Among the less common – but more spectacular – inclusions we find diamond crystals: yes, you read that right, diamond inside diamond. They generally have a well-formed octahedral shape and are transparent; other types of crystals can also be found, although they generally have different shapes and colors: we are talking, for example, of red garnets, green olivines or black graphite. These types of inclusions are very important as they provide more than certain proof that your diamond is natural.

Clearly visible triangular trigones present on rough diamond of Kimberlite, a rock that carries these gems from the heart of the earth’s mantle to the surface. If the cutter chooses to leave part of these stingrays, they will be clearly visible if observed with a gemological triplet.
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Twin gemstone called “maclè”, numerous stingrays are found on its surface.
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Even the stingrays – which can be found along the belt or the apices of the diamonds – are relatively common characteristics of purity: they have more or less extended dimensions and are characterized by the typical triangular shape. They are formed during the growth of the raw crystal and if they are observed it is because the one who cut the diamond has decided to leave a trace of the “life history” of the gem.

But what are all these purity characteristics for commercial purposes?

Keep on…

Written by Giulia Lombardo