Properties of Apophyllite

Apophyllite is a mineral belonging to the family of phyllosilicates. It is typically found in volcanic rocks and is characterized by its transparent to translucent appearance and crystal formations.

Image of apophyllite mineral
Credit: Rob Lavinsky, iRocks.com - CC-BY-SA-3.0, via Wikimedia Commons

The following table provides a comprehensive list of apophyllite 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 Apophyllite Properties
Physical Properties
Metric
Chemical FormulaKFCa4Si8O20·8H2O
Molar Mass907.2 g/mol
Crystal SystemTetragonal
Mohs Hardness4.5 - 5
Density2350 kg/m3
ColorUsually white, colorless; also blue, green, brown, yellow, pink, violet
DiaphaneityTransparent to translucent
LusterVitreous (pearly)
CleavagePerfect on (001)
FractureUneven
StreakWhite

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.