The diamonds which most of us see are cut or faceted. In the rough, diamonds are well-formed octahedral (eight-sided) crystals. In this, their natural state, they are truly a thing of beauty because of their symmetry and interesting growth features.

Upon close examination such rough diamonds show growth texture made up of triangular pits, called trigons. Some are too small for the naked eye to see. It is this feature which gives a rough diamond a scaly look, with a hard, slippery feel. Trigons appear as a result of the crystal's atomic structure. The carbon atoms of which a diamond is composed bond symmetrically. They form cubic structures even though the external shape of the diamond may appear in a variety of shapes.

The face of a diamond is built of stacked crystalline layers which appear as step-like structures along the diamond's edges. No other crystal gem, natural or man-made, resembles a diamond's external appearance.