INCLUSIONS FREQUENTLY SEEN IN CVD GROWN SYNTHETIC DIAMONDS

Black inclusions (likely non-diamond carbon) ranging in size from pinpoints to large ‘crystals’ are a common feature in CVD grown diamonds.

Black inclusions (likely non-diamond carbon) ranging in size from pinpoints to large ‘crystals’ are a common feature in CVD grown diamonds.

A comet-like tail formed as growth continued on after a black inclusion disturbed the structure of this CVD diamond.

A comet-like tail formed when growth continued after the appearance of a black inclusion disturbed the formation of this CVD diamond.

Feathers are commonplace in CVD grown diamonds. Their appearance can usually be described as bright, whitish, frosted or thick.

Feathers are commonplace in CVD grown diamonds. Their appearance can usually be described as bright, whitish, frosted or thick.

The series of bright white feathers in this CVD diamond are a familiar scene but provide little assistance in the identification of origin.

A more magnified view of the bright white feathers pictured to the left.

A cloud of black inclusions arranged in a single plane provides a trace to the layered growth and stop-start cycles of CVD synthesis.

A planar cloud of small whitish inclusions with ‘tails’ provides a clue to the direction of growth of this CVD diamond. This feature likely developed during the stop-start cycle of CVD growth.

A single sharp plane of graining is a familiar scene in faintly colored CVD grown diamonds.  Though origin identification cannot be proved solely on planar inclusions and graining, they are distinct remnants of CVDs layered past.

A single sharp plane of graining is a familiar scene in faintly colored CVD grown diamonds.  Though origin identification cannot be proved solely on planar inclusions and graining, they are distinct remnants of CVDs layered past.

INCLUSIONS FREQUENTLY SEEN IN HPHT GROWN SYNTHETIC DIAMONDS

By far, the most frequent characteristic in HPHT grown synthetics are opaque metallic inclusions; a remnant of their origin in molten metal flux.

A more magnified view of the metallic inclusions pictured to the left.

Rod shaped metallic flux inclusions of varying sizes are frequently seen in HPHT grown synthetic diamonds. Flat, tabular, or vaguely triangular shapes are common.

This 70x+ magnified view illustrates the reflective luster of the metallic flux inclusion. Fiber optic illumination can be useful when examining the opacity and luster of included crystals. 

Another example of a rod shaped metallic flux inclusion in a HPHT grown synthetic diamond.

When metallic flux inclusions are large enough, the iron and nickel content reveals itself in the form of magnetism. The origin of this 0.01 carat diamond is confirmed by its attraction to a magnet.

Another example of a flat metallic flux inclusion in a HPHT grown synthetic melee diamond.

Another example of a flat metallic flux inclusion in a HPHT grown synthetic melee diamond.

Another example of a rod shaped metallic flux inclusion in a HPHT grown synthetic melee diamond.

Occasionally black and white dendrite-like inclusions are present in HPHT grown diamonds.

Occasionally black and white dendrite-like inclusions are present in HPHT grown diamonds.

Occasionally thin hair-like needles are present in HPHT grown diamonds like in this 0.005 carat.