Properties of Beryl

Beryl is a mineral composed of beryllium aluminum cyclosilicate, with the chemical formula Be3Al2Si6O18 . It is a relatively rare and precious gemstone, and it comes in a variety of colors, each with its own gemstone name. The most well-known varieties of beryl include:

  • Emerald: Green beryl colored by chromium and vanadium impurities.
  • Aquamarine: Blue to greenish-blue beryl, often resulting from iron impurities.
  • Morganite: Pink to peach-colored beryl, usually caused by manganese impurities.
  • Heliodor: Yellow to greenish-yellow beryl, typically due to iron impurities.
  • Goshenite: Colorless or white beryl, the purest form of the mineral.
Image of beryl mineral
Credit: Parent Géry, Public domain, via Wikimedia Commons

The following table provides a comprehensive list of beryl properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).

Note: click on the icon to switch between Metric and Imperial units.

Table of Beryl Properties
Physical Properties
Metric
Chemical FormulaBe3Al2Si6O18
Molar Mass537.5 g/mol
Crystal SystemHexagonal
Mohs Hardness7.5 - 8.0
Density2640 kg/m3
ColorGreen, blue, yellow, colorless, or pink
DiaphaneityTransparent to subtranslucent
LusterVitreous, resinous
Cleavage[0001] imperfect
FractureBrittle, conchoidal
StreakWhite
Thermal PropertiesMetric
Melting Point1650 °C

Note: unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)

Related Pages
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017.