Beryl

Beryl
Beryl09.jpg
Three varieties of beryl: morganite, aquamarine and heliodor
General
CategoryCyclosilicate
Formula
(repeating unit)
Be3Al2(SiO3)6
Strunz classification9.CJ.05
Crystal systemHexagonal
Crystal classDihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Space groupP6/mcc
Unit cella = 9.21 Å, c = 9.19 Å; Z = 2
Identification
Formula mass537.50 g/mol
ColorGreen, blue, yellow, colorless, pink and others
Crystal habitPrismatic to tabular crystals; radial, columnar; granular to compact massive
TwinningRare
CleavageImperfect on {0001}
FractureConchoidal to irregular
TenacityBrittle
Mohs scale hardness7.5–8
LusterVitreous to resinous
StreakWhite
DiaphaneityTransparent to translucent
Specific gravityAverage 2.76
Optical propertiesUniaxial (-)
Refractive indexnω = 1.564–1.595
nε = 1.568–1.602
Birefringenceδ = 0.0040–0.0070
PleochroismWeak to distinct
Ultraviolet fluorescenceNone (some fracture filling materials used to improve emerald's clarity do fluoresce, but the stone itself does not). Morganite has weak violet fluorescence.
References[1][2][3][4]

Beryl (əl/ BERR-əl) is a mineral composed of beryllium aluminium cyclosilicate with the chemical formula Be3Al2(SiO3)6. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring, hexagonal crystals of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, red (the rarest), and white. Beryl is also an ore source of beryllium.[5]

Etymology

The name "beryl" is derived (via Latin: beryllus, Old French: beryl, and Middle English: beril) from Greek βήρυλλος beryllos which referred to a "precious blue-green color-of-sea-water stone"; akin to Prakrit verulia, veluriya ("beryl").[6] The term was later adopted for the mineral beryl more exclusively.

When the first eyeglasses were constructed in 13th century Italy, the lenses were made of beryl (or of rock crystal) as glass could not be made clear enough. Consequently, glasses were named Brillen in German [7] (bril in Dutch and Briller in Danish).

Other Languages
العربية: بيريل
aragonés: Berilo
asturianu: Berilu
azərbaycanca: Beril
беларуская: Берыл
беларуская (тарашкевіца)‎: Бэрыль (мінэрал)
български: Берил
bosanski: Beril
català: Beril
Чӑвашла: Берилл
čeština: Beryl
dansk: Beryl
Deutsch: Beryll
eesti: Berüll
Ελληνικά: Βήρυλλος
español: Berilo
euskara: Berilo
فارسی: گوشنیت
français: Béryl
Gaeilge: Beiril
galego: Berilo
한국어: 녹주석
Հայերեն: Բերիլ
हिन्दी: बेरिल
hrvatski: Beril
Ido: Berilo
italiano: Berillo
עברית: בריל
ქართული: ბივრილი
kaszëbsczi: Beril
қазақша: Берилл
Latina: Beryllus
latviešu: Berils
lietuvių: Berilas
magyar: Berill
മലയാളം: അക്വാമറൈൻ
မြန်မာဘာသာ: မြ
Nederlands: Beril
日本語: 緑柱石
norsk: Beryll
norsk nynorsk: Beryll
oʻzbekcha/ўзбекча: Berill
Plattdüütsch: Beryll
português: Berilo
română: Beril
русский: Берилл
саха тыла: Берилл
Scots: Beryl
සිංහල: තරිප්පු
Simple English: Beryl
slovenčina: Beryl
slovenščina: Beril
српски / srpski: Берил
srpskohrvatski / српскохрватски: Beril
suomi: Berylli
svenska: Beryll
தமிழ்: பெரில்
ไทย: เบริล
ತುಳು: ಪಚ್ಚೆ
Türkçe: Beril
українська: Берил
ئۇيغۇرچە / Uyghurche: يېشىل ياقۇت
Tiếng Việt: Beryl
Wolof: Beril
中文: 綠柱石