CaAlBeSi2460 · H
Milarite, a member of the osumilite group, is exceedingly rare at MSH.
It fluoresces blue-white under SW. It bears very close ressemblance to pectolite and is easily overlooked.
Color is usually white to colorless.
Luster is vitreous to silky to dull.
Diaphaneity is translucent to opaque.
Crystal System is hexagonal; 6/mcc
Crystal Habits include aggregates of crude hexagonal prisms
to 3mm on pectolite.
Fracture is conchoidal to uneven.
Hardness is 5.5 – 6.
Specific Gravity is approximately 2.55 g/cm
Streak is white.
Associated Minerals include aegirine, apophyllite group, calcite,
fluorite, pectolite and poudretteite.
Distinguishing Features: Crystal habit and its triated nature.
Origin: Named in 1870 after its occurrence at Val Millar, Switzerland.
MinRec 21:322 (1990), Dana 8:1277-1278 (1997)
DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE: