A well-cut diamond can make light perform in breathtaking ways, resulting in a magnificent display of three important diamond attributes: brilliance, fire and scintillation.

Brilliance is the combination of all the white light reflections from the surface and the inside of a diamond.  It gives a polished diamond its brightness.  

Fire is the word for the flashes of colour you see in a polished diamond.  

Scintillation describes the flashes of light you see when the diamond, the light or the observer moves.

The three major parts of a polished diamond, top to bottom, are the crown, the girdle, and the pavilion.  The crown and the pavilion - and sometimes the girdle - have small, flat, polished surfaces called facets.  Some polished diamonds also have a flat facet at the bottom of the pavilion, called the culet.  

Brilliant cut - Cutting style with triangular or kite-shaped facets that radiate from the centre toward the girdle.

Standard round brilliant - A round brilliant-cut stone with 57 or 58 facets.  Often called a full cut.

Single cut - A round stone with 17 or 18 facets.

Fancy cut - Any gemstone shape other than round.

Step cut - A cutting style that features long, narrow facets in rows (usually three) parallel to the girdle on both the crown and pavilion.

Baguette - A small, four-sided step cut that's rectangular, square, or tapered.