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Beryl is a most alluring and popular mineral. It occurs in a diversity of colors, and has several important gemstone varieties. The green variety, Emerald, is one of the most precious gems. Only green Beryl with a deep green color is called Emerald; light green Beryl is simply " Green Beryl" (or Heliodor if it has a yellowish color.) Aquamarine, another important gemstone, is the greenish-blue to blue variety of Beryl. Green Beryl from certain localities can be heat treated to produce sky-blue Aquamarine.
Other popular gem varieties of Beryl are the pink Morganite, and the yellow Heliodor and Golden Beryl. A deep red variety of Beryl, known as Red Beryl (or Bixbite) is extremely rare, and only comes from two localities in Utah. When in good specimens, Red Beryl commands an outstanding premium and is very difficult to obtain.
Pure Beryl is colorless. However, a wide range of impurities cause
the diverse amount of colors and many varieties. The green color in Emerald is usually caused by traces
of the element chromium, and the blue color of Aquamarine usually by iron. Beryl is naturally transparent, however inclusions and impurities may make it opaque. All gemmy transparent varieties are highly valued, but the other forms of Beryl in opaque crystals are much more common. Some of the largest natural crystals known are of Beryl, with enormous crystals having been found in several pegmatite occurrences. |
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Chemical Formula |
Be3Al2Si6O18 |
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Composition |
Beryllium aluminum silicate, occasionally with some sodium, lithium, and cesium |
| Variable Formula |
(Be,Na,Li,Ce)3Al2Si6O18 |
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Color |
Light to emerald green, light to deep sky-blue, blue-green, yellow, pink, purple, red, orange, brown, colorless, white, and gray. May also be multicolored blue, green, yellow, or white, and may also have deeper color highlights on one crystal end. |
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Streak |
Colorless |
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Hardness |
7.5 - 8 |
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Crystal System |
Hexagonal |
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Crystal Forms
and Aggregates |
Beryl often crystallizes in perfect, six-sided hexagons. Crystals are usually as individual prismatic hexagons. Crystals may be enormous in size; some 30 foot long (8 meter), well-crystallized examples have been found. Beryl may also be short, stubby crystals, and occasionally in tabular crystals and plates.
The bases of Beryl crystals are usually flat; pyramidal terminations are rare. Also occurs in columnar aggregates, in distorted etched crystals, and massive. Occasionally in drusy or platy aggregates and as bundles of thin, long crystals.
Crystals may be striated lengthwise. |
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Transparency |
Transparent to opaque |
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Specific Gravity |
2.6 - 2.9 |
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Luster |
Vitreous, waxy |
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Cleavage |
3,1 - basal |
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Fracture |
Uneven to conchoidal |
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Tenacity |
Brittle |
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Other ID Marks |
Occasionally fluorescent yellow, light blue, purple, pink, or red. |
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Complex Tests |
Insoluble in acids. |
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In Group |
Silicates; Cyclosilicates |
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Striking Features |
Crystal form and hardness |
| Environment |
Beryl is most well-known from granite pegmatites. It can also be found in metamorphosed mica schists and in igneous rhyolite deposits.
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| Rock Type |
Igneous, Metamorphic |
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Popularity (1-4)
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1 |
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Prevalence (1-3)
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2 |
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Demand (1-3) |
1 |
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- Sky blue to bluish-green variety of Beryl.
- Mineral very similar to Beryl but with some of the rare element scandium replacing some of the aluminum in its chemical structure. Its chemical formula is Be3(Al,Sc)2SiO6. Although Bazzite is often considered to be a variety of Beryl, it is scientifically recognized as an individual mineral species.
- Occasionally used to describe the rare form of Red Beryl from Utah. Its name was in honor of mineralogist Maynard Bixby (1853 – 1935), a well known explorer of the Thomas Range in Utah. The name Bixbite is no longer suggested and accepted, due to confusion of the term with the mineral Bixbyite, which is an entirely different mineral named after Maynard Bixby.
- Golden yellow to orange-yellow variety of Beryl. See the gemstone Golden Beryl for additional information.
- Colorless or white variety of Beryl. See the gemstone Goshenite for additional information.
- Pale green variety of Beryl. Green Beryl is distinguished from Emerald which is deeper green, and from Heliodor which is greenish-yellow to yellow. Many authorities don't recognize Green Beryl as a variety and just include it as a form of Heliodor.
- Greenish-yellow to yellow variety of Beryl. The term Heliodor may also be used to describe light green, orange, and brown Beryl, and can be interchangeable with Golden Beryl.
- Pink to light purple variety of Beryl. See the gemstone Morganite for additional information.
- Pezzottaite is a newly identified raspberry-red mineral very similar to Beryl
Pezzottaite, but contains lithium as well as some of the rare element cesium replacing some beryllium in its chemical structure. It is a newly identified mineral, first recognized by the IMA in
2003. Although
Pezzottaite was originally regarded as a variety of Beryl, it is now
scientifically recognized as an individual mineral species.
- Term used to distinguish the gemmy transparent forms of Beryl from the more common opaque forms.
- Deep red form of Beryl that comes from Utah.
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Beryl forms some of the most well-known and prized gemstones. The deep green
variety Emerald is one of the most valuable gems. Aquamarine, a
semi-precious gem, is the most popular light blue gem. Morganite, Golden Beryl, and Heliodor are also used as gems, though Goshenite and Red Beryl are less frequently faceted into gemstone cuts.
Beryl is a very important collector's mineral, and gemmy crystals can be very valuable. Due do its rarity, Red Beryl is rarely faceted as collectors prize its natural crystal form.
Beryl is also an important industrial mineral, and is mined for the element beryllium (formerly known as glucinium). Beryl is the main ore or beryllium. Beryllium is a very tough metal, and is sometime used in alloys to strengthen other metals.
The gemstone applications of the Beryl varieties are discussed in greater detail in their own dedicated gemstones pages. Make sure to also see the gemstone section on Beryl, Emerald, Aquamarine, Morganite, Golden Beryl, and Goshenite.
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Beryl has many important localities worthwhile of being mentioned. As not to overwhelm the reader with localities, we have separated the Emerald and Aquamarine varieties on their own dedicated page with more detailed locality information.
Excellent Morganite comes from northern Afghanistan, in the Provinces of Laghman, Konar, Nuristan, and Nangarhar (especially Darra-i-Pech). The pegmatites of the Doce Valley in Minas Gerais Brazil also produce fine Morganite, notably at the Urucum mine, Galiléia; and Golconda, Governador Valadares. The finest Morganite in the U.S. comes from Pala and Mesa Grande Districts in San Diego Co., California. Especially of note at Pala are the White Queen Mine, the Elizabeth R. Mine, the Oceanview Mine, the Stewart Mine, and the Katerina Mine. In Connecticut, Morganite was found in the Gillette Quarry, Haddam Neck, Middlesex Co.
Some of the finest Heliodor and Golden Beryl come from the Doce Valley in Minas Gerais, Brazil, at São José da Safira, and at the Itatiaia mine in Conselheiro Pena. A Russian Heliodor occurrence is the Mursinska Mine in Yekaterinburg, in the Ural Mountains. Outstanding oddly-shaped etched Heliodor (as well as transparent Green Beryl), is famous from Volodarsk-Volynskii, Zhitomir Oblast, Ukraine, and these specimens have made their way into the finest collections. In the U.S., Heliodor comes from the Slocum Prospect, East Hampton, Middlesex Co., Connecticut.
Goshenite is found in many of the Aquamarine pegmatite localities, especially in the Shigar Valley, Skardu District, Baltistan, Pakistan; Mt. Xuebaoding, Pingwu, Sichuan Province, China; the Minas Gerais, Brazil gem pegmatites; Mogok, Burma (Myanmar); and the Erongo Mountains, Namibia. The name of Goshenite originates from the locality of Goshen, Hampshire Co., Massachusetts, but this locality has produced few specimens of interest.
Red Beryl only comes from Utah, in both the Wah Wah Mts, Beaver Co.; and as smaller crystals in the Thomas Range, Juab Co.
In the U.S., some of the New England pegmatite localities were known to have produced giant Beryl crystals. Notable among these localities are the Bumpus Quarry, Albany, Oxford Co., Maine; the Tripp No. 1 Quarry, Alstead, Cheshire Co., New Hampshire; and the Palermo No. 1 Mine, Groton, Grafton Co., New Hampshire.
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Apatite - Significantly softer (5).
Quartz - Softer (7), usually terminated, and crystals striated horizontally (whereas Beryl striated vertically).
Feldspars - Softer (6), have good cleavage.
Topaz - Different crystal forms. (Though difficult to distinguish in massive form).
Tourmaline - Different crystals forms, crystals heavily striated.
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The images below represent all forms and varieties of Beryl except for the Emerald and Aquamarine varieties. These varieties have their own dedicated page with more photos.
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