General Information:
Chemical Formula:Na2Ca5Al12Si20O64·27(H2O)
Composition:(Molecular Weight = 2,642.23 gm)Sodium 1.74 %
NaCalcium 7.58 %
CaAluminum 12.25 %
AlSilicon 21.26 %
SiHydrogen 2.06 %
H Oxygen 55.10 %
O Empirical Formula: Na2Ca5Al12Si20O64·27(H2O)
IMA Status:Approved IMA 1962
Name Origin:Named after its locality in Garron Plateau, Northern Ireland.
Physical Properties: Cleavage:[???] Good, [???] Good
Color:colorless or white.
Density:2.1 - 2.2, Average = 2.15
Diaphaniety:Transparent to Translucent
Habits:Acicular - Occurs as needle-like crystals., Massive - Fibrous - Distinctly fibrous fine-grained forms., Radial - Crystals radiate from a center without producing stellar forms (e.g. s tibnite)
Hardness:4-5 - Fluorite-Apatite
Luster:Vitreous (Glassy)
Streak:white
More details...
