Yellow Beryl (Heliodor)

Physical Properties

Hardness: 7.5-8.0 on Mohs scale; Color: Pale yellow to golden-yellow; Luster: Vitreous; Crystal System: Hexagonal; Specific Gravity: 2.63-2.90; Cleavage: Indistinct/Imperfect.

Formation & Geological History

Formed in granitic pegmatites and metamorphic rocks (mica schists) through hydrothermal processes. The yellow color is caused by trace amounts of iron (Fe3+) ions replacing aluminum in the crystal lattice.

Uses & Applications

Primarily used as a gemstone in high-end jewelry (rings, pendants) and as a collector's mineral specimen. Historically used as a source of beryllium metal.

Geological Facts

The name 'Heliodor' is derived from the Greek words 'helios' (sun) and 'doron' (gift), meaning 'gift from the sun'. It is in the same mineral family as Emerald and Aquamarine.

Field Identification & Locations

Identify by its high hardness (will scratch glass easily), hexagonal crystal habit if rough, and distinctive vitreous luster. Commonly found in Brazil, Madagascar, Namibia, and Russia.

Identified on: 4/14/2026

Mode: Standard