Interestingly macles are first formed as octahedrons, but early in the crystals growth extra pressure has been applied to one side, causing the crystal to grow into this  natural triangular formation, most mines have macles.

Its atomic structure shows a twinning effect and the term Macle is French for Twinned crystal.

Note: The unique moonscape surface (hexagonal pits) that is unique to  Argyle Diamonds, is clearly visible on the large Macle, whereas the Argyle Cognac Macle has none. The two smaller white Macles are of South African origin and will more often have Trigon markings (inverted V’s).

We have macle stones ranging from 0.40ct to 2.50cts. As an indication the large macle weighs 2.20ct and measures 10mm x 10mm