Heliodor
Heliodor is a cyclosilicate mineral valued for its hardness and gem potential.
About Heliodorextended article
Heliodor is the yellow to greenish-yellow gem variety of beryl, coloured by traces of iron. Its name, from the Greek for 'gift of the sun', captures its bright golden tones; the term is generally used for the more greenish-yellow stones, with pure yellow material sometimes called golden beryl.
Properties
Like all beryl it is hexagonal, hard (7.5–8) and forms clean prismatic crystals, frequently large and well terminated. Heliodor is typically very transparent and free of the fractures that trouble emerald.
Occurrence
Notable sources include Ukraine, Brazil, Madagascar, Namibia and the United States. It belongs to the same species as aquamarine, morganite and colourless goshenite.
About Heliodor
Heliodor belongs to the cyclosilicate class in the beryl group and has the chemical formula Be3Al2Si6O18. It crystallizes in the hexagonal system and ranks among the harder species, with lasting durability.
Identification & care
Specimens usually show prismatic hexagonal; typically well-formed striated crystals. Its color is typically yellow to golden-yellow and yellow-green. The luster is vitreous, the streak is white, and specimens range from transparent to translucent. The cleavage is imperfect basal. The fracture is conchoidal, which aids identification.
Collector context
Collector notes
Among gem-quality species, Heliodor holds a distinguished position in collections.
Frequently asked questions
What is Heliodor?
Heliodor is a cyclosilicate mineral valued for its hardness and gem potential.
What is the chemical formula of Heliodor?
The chemical formula of Heliodor is Be3Al2Si6O18.
What crystal system does Heliodor belong to?
Heliodor crystallises in the Hexagonal crystal system.
References & databases
Mindat.org is the world’s largest open mineralogy database. Our descriptions are written independently and fact-checked.