What is a pink diamond called?

A type of inclusion. A crystal is a mineral deposit trapped inside the diamond.

CULET
Small facet on the point of the pavilion of a brilliant-cut diamond or on the keel of a step cut; fashioned to reduce the risk of damage.

CUT
(1) shape and style of a polished diamond, such as a round brilliant or an emerald cut. (2) proportions and finish of a diamond. One of the 4 Cs, also called make.

DEPTH
The distance between the table and the culet as measured in millimeters.

DEPTH PERCENTAGE
The depth of the diamond divided by the average width expressed as a percentage.

DIAMOND
Mineral composed essentially of carbon crystallized at extremely high temperatures and pressures; in nature, diamonds form 150 to 200km (93 to 124 miles) or more below the earth's surface. Diamond is the hardest of all known natural substances (10 on the Mohs scale); its refractive index is 2.417, dispersion 0.044, specific gravity 3.52, and its lustre is adamantine. Diamond ranges from colourless to yellow, brown, gray, orange, green, blue, white, black, purple, pink and extremely rarely, red. Transparent and near-colourless is a desirable colour, diamond is a highly valued gemstone.

EGL
European Gemological Laboratory - EGL has franchises in a number of cities around the world which grade diamonds.

DISPERSION
Separation of white light into spectral colours, each of which vibrates at a different frequency. Also called fire.

ENHANCEMENT
Any post-recovery process which alters the appearance, especially the colour or clarity of a natural diamond or other gem material. Coating, fracture filling, irradiation, heating (annealing) and lasering are all forms of enhancement. Also called treatment.

EYE-CLEAN
In clarity grading eye-clean diamonds should have no inclusions that are visible through the crown to the unaided eye.

FACET
Flat polished surface on a finished diamond.

FANCY SHAPE
Any cut other than a round brilliant or single cut. Traditional fancy cuts include the marquise, emerald cut, heart shape, oval shape, pear shape, half-moon, kite, triangle and various modified brilliant cuts.

FANCY COLOUR
Any naturally coloured diamond with a noticeable depth of bodycolour considered to be rare or attractive. Red and green are the rarest fancy colours, followed by purple, violet, orange, blue and pink. Yellow, sometimes called canary diamonds and greenish yellow diamonds are more common. Light, or low-saturation coloured diamonds other than yellow or brown, may be classed as fancies, but, in the GIA colour-grading system, yellows and browns must be darker than the Z master diamond to merit a fancy grade. Fancy colour grades are decribed as faint, very light, light, fancy light, fancy, fancy intense and fancy dark in the GIA system. Treated diamonds are not considered fancy diamonds, but are sometime referred to as 'treated fancy diamonds' in the trade.

FEATHER
Cleavage or fracture; may be transparent, but usually has a whitish appearance when seen at right angles to the break. Also called a gletz.

FINISH

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