Most Diamond certificates contain comments. Here is a small glossary that contains definitions and terminology.
Crystal : a mineral deposit found inside the diamond, either alone or in groups. The crystal may be colored or colorless, but usually appears black in overhead daylight.
Pinpoint : a very small crystal, often whitish in color. When clustered together, these pinpoints can form a cloud.
Cloud : a tide grouping of pinpoint inclusions. The individual pinpoints are often impossible to see under 10x magnification, but the cloud they form can be.
Cavity : an opening or depression in the surface of the diamond, usually caused by a natural flaw in the rough stone.
Chip : shallow nick in the surface of the diamond, often created during cutting.
Bruise : a chip on the surface of the diamond that may include root-like feathers radiating into the diamond.
Feather : a fracture that often has fine lines radiating from it , resembling a feather. Feathers usually a appear white or transparent, depending on the viewing angle.
Needle : very fine elongated inclusion. Similar in appearance to a feather, without the radiating lines.
Twinning wisps : a flat ribbon of pinpoints or clouds, caused by natural distortion created during the growing of the crystal.
Natural : small remains of the original rough stone’s surface, left unpolished on the surface of the finished diamond.
Indented natural : A natural that leaves an actual depression or indention on the surface of the finished diamond
Extra facet :any facet that is not a part of the shape’s standard cut. Usually created by the cutter due to a limitation or flaw in the original rough stone.
Read about diamond cut/polish/symmetry