Emerald is the rich green variety of the mineral beryl (Be3Al2(SiO3)6) and is one of the most prized gemstones in history.

Here’s a detailed description:

Appearance & Color

• Characteristic vivid green to bluish-green color caused by trace amounts of chromium, vanadium, or both.

• The most valuable stones have a deep, saturated green with uniform color distribution.

• Often contains internal features called jardin (“garden” in French) — inclusions that are accepted as part of its natural identity.

Physical Properties

• Hardness: 7.5–8 on the Mohs scale, but can be brittle due to inclusions.

• Luster: Vitreous (glassy).

• Cleavage: Poor, making cutting challenging.

• Refractive Index: ~1.565–1.602.

• Specific Gravity: ~2.67–2.78.

Geological Occurrence

• Forms in hydrothermal veins or metamorphic rocks where beryllium-bearing fluids meet chromium- or vanadium-rich rocks.

• Major sources: Colombia (famous for pure, intense greens), Zambia (often slightly bluish-green), Brazil, Ethiopia, Afghanistan.

Special Notes

• Many emeralds are oil-treated to improve clarity — this is common and generally accepted if disclosed.

• The term “emerald cut” comes from the rectangular step-cut style developed to protect the gemstone from damage.

• In lore, emeralds are associated with renewal, fertility, and truth.