Gemstone Cuts & Shapes
Whether you are shopping for jewelry or designing a custom piece, understanding gemstone cuts and shapes can help you appreciate both the artistry and value of a stone. Some cuts maximize brilliance and sparkle, while others emphasize color, pattern, or unique optical effects.
Cabochons
A cabochon — often shortened to “cab” — is a gemstone that has been shaped and polished rather than faceted. Cabochons usually feature a smooth, rounded top with a flat or slightly curved bottom.
Cabochons are ideal for stones that display a strong color (lapis lazuli or turquoise), have interesting patterns (agates or malachite), exhibit chatoyancy or cat’s eye effect (tiger eye), star asterism (star sapphire, for example), or have opalescence.
Faceted Stones
Faceted stones are cut with multiple flat surfaces called facets. These facets reflect and refract light, creating brilliance, fire, and sparkle.
Faceting can increase sparkle, improve brilliance, enhance apparent color, make a gemstone appear more lively, and increase value for certain gem materials. Common faceted stones include: diamond, sapphire, ruby, aquamarine, amethyst, citrine, garnet, and topaz. All are transparent and make the best use of faceting.
A Few Others!
Doublets
A doublet is a gemstone made from two layers bonded together. The top layer is typically a thin layer of an attractive gemstone. The bottom layer provides support, durability, or can modify the color of the upper stone. It can also make the best use of an expensive stone. Common doublets include turquoise (you often see a black backing to both make the stone higher and more durable) and opals (a black backing makes the fire really “pop”).
Triplets
A triplet is similar to a doublet but consists of three layers. Typically: a thin gemstone slice in the middle, a dark backing layer underneath, and a clear protective cap on top, often quartz or glass. The advantages are similar to doublets, with an additional advantage of providing a protective cap over a delicate stone. Opals are probably the most common triplet.
Popular Gemstone Shapes
Gemstones can be cut into many different shapes. Shape refers to the outline of the stone when viewed from above.
Common cuts include: round, free form, oval, pear, emerald, cushion, marquis, princess, trillion, and heart shape.