The old cut was invented during the nineteenth century and is the direct predecessor of the brilliant cut, which has since become the cut that is most frequently used for diamonds today. The old cut was designed with a different number and arrangement of facets than later ones has become common on diamonds. For this reason, diamonds drawn in the old cut do not look as fiery and bright as diamonds. Various other historical cuts of diamonds are sometimes found in older jewelry; Nowadays, all of them are grouped under the general title of "Diamond old cut stones".

Olivine is more commonly known as "peridot" in the jewelry world. Olivine received its name because of its pale yellow green color, close to the olive one; it numbers among the few precious stones that occur only in one color. Although olivine is not an extremely hard mineral, this stone has been valued as a precious jewel since ancient times. The deposits are located in northern Burma, Australia and Brazil. Olivine has also been identified as a component of meteorites.

Onidi is the name given to deep black chalcedony, which is a variety of quartz. Onyx is most frequently found as a multilayer stone: the material consists of many layers of black substrate and white overlapping layers. Chalcedony in its natural state can be dull or have a waxy glow. Stones with varicolor layers can be boiled in sulfuric acid. This treatment gives them a uniformly black appearance.

Orient pearl is the technical term for authentic pearls and/ or natural pearls that form inside oysters without human intervention. The cells that produce mother of pearl are normally found on the inner surface of the shell, for the growth of which they are responsible. Orienting the beads can form when some of these cells move away inward from the bivalve. This can occur, for example, when a parasite drills through the shell into the animal's body, or when a foreign body penetrates between the halves of the shell and injures the animal inside the shell. The mere penetration of a pebble or grain of sand inside the shell is not enough to cause the formation of an oriental pearl.

As its name explicitly states, the oval cut is a smooth oval shape for gems. This cut is derived from the brilliant cut. The main element of the oval cut is the oval table with the surrounding facets.