Common shapes are "Round", "Pear", "Oval", "Princess", but there are dozens of created cuts by artisans. Shapes that look different than the classic round diamonds are often referred to as "fancy cut diamonds"

One carat weighs 200 milligrams. Sometimes this is called the size of the diamond

Most diamonds don't have color and are transparent. The little color that is left is divided into color grades ranging from D-Z. The value D has the least color, whilst in grade G and up the color becomes slightly noticable.
Fancy color diamonds are beyond this scale and have a distinct color such as "yellow", "blue" and "pink". Fancy color diamonds are very rare.

Internal dots or marks are very common in natural diamonds. These are tiny fragments that can look like dots or lines and are usually only visible through a magnifying glass. The less obstruction the light has, the more valuable the diamond. The grading values are (few to many inclusions): FL (flawless), IF (internally flawless), VVS1 (very very slightly included), VVS2, VS1 (very slightly included), VS2, SI1 (slightly included), SI2, SI3, I1 (included), I2, I3

Each diamond is unique, and the result of the diamond cut and polish is graded by an value we call "Make". For round diamonds this is the same as the "cut grade" the grading lab may give. This includes a general grade based on proportions, symmetry and polish. The values for this grade range from Ideal/Excellent to Poor.

The gemologist at the grade laboratorium decide what grade to the give the different properties of the diamond. However, different laboroties may have slightly different standards. The most common labs are "AGS", "EGL USA", "GIA", "HRD" and "IGI".