silicates
Beryl
Be3Al2Si6O18
- Also known as
- emeraldaquamarinemorganiteheliodorgoshenite
- Crystal system
- hexagonal
- Hardness
- 7.5–8 on the Mohs scale
- Lustre
- vitreous
- Colour
- Colourless when pure; green, blue, pink, yellow or red with impurities
- Where it forms
- In granite pegmatites and in some metamorphic rocks. Beryllium is a rare element and concentrates only in the last fluids to crystallise from a granite.
- Chiefly from
- ColombiaBrazilMadagascarZambiaAfghanistan
Why it is that colour
Pure beryl is colourless. Chromium or vanadium gives emerald, iron gives aquamarine and heliodor, manganese gives morganite and red beryl. One mineral, six gem names.
Safety
Solid beryl is safe to handle. Beryllium compounds are seriously toxic when inhaled, and chronic beryllium disease is a well-documented occupational lung illness. Cutting, grinding or drilling beryl without extraction is a genuine hazard, which is why lapidaries take it seriously.
Where it comes from
Emerald from Colombia and Zambia; aquamarine largely from Brazil and now Nigeria; much fine material from Afghanistan and Pakistan, where mining is small-scale and the trade has been linked to conflict financing.
Historical use
The principal source of beryllium, a metal used in aerospace alloys and in nuclear applications. Historically the clear variety was ground into lenses, which is how a gemstone ended up giving its name to eyeglasses in several European languages.
Recorded as history and attributed where possible. That a stone was used for something establishes that people used it, not that it worked.
What is attributed to it, and since when
Known and named in antiquity, and the source of the English word "brilliant" by way of the spectacles ground from clear beryl in medieval Europe — which is also where German Brille, meaning glasses, comes from. Individual varietal meanings are mostly modern.
Described, not endorsed. Dating a claim is not the same as assessing it — but an association that first appears in a book published in 1985 is not an ancient inheritance, whatever the label says. A sincere account of feeling better is compatible with the stone doing nothing — see the placebo effect.
Worth knowing
Beryl is the best single illustration of what "variety" means in this collection. Emerald and aquamarine are the same mineral. They have the same formula, the same structure, the same hardness and the same crystal habit. The difference is a trace of chromium in one and a trace of iron in the other, present at levels that would round to zero in a chemical analysis.
Emerald has been among the most valuable substances on earth for three thousand years. Aquamarine is affordable. The gap between them is a few atoms per thousand, and everything else about that gap is human.
Identity checked against IMA-CNMNC master list, June 2025.