Beryl occurs very rarely at Mont Saint-Hilaire. It is very similar to fluorapatite in the hornfels environment, from which it is difficult to distinguish visually.
PHYSICAL CHARACTERISTICS:
- Color is usually pale yellow to yellowish-green.
- Luster is vitreous.
- Diaphaneity is transparent.
- Crystal System is hexagonal; P6/mcc.
- Crystal Habits include hexagonal prisms terminated by the
{0001} pinacoid and small pyramidal faces. - Cleavage {001} is indistinct.
- Fracture is uneven to subconchoidal.
- Hardness is 7.5 – 8.
- Specific Gravity is approximately 2.6 g/cm3.
- Streak is white.
- Associated Minerals include albite, ancylite, chlorite group,
molybdenite, siderite and UK #56. - Distinguishing Features: Crystal habit.
- Origin: Known since antiquity, name comes from the Greek
beryllos, an ancient term for a blue-green gem.
Dana class # | 61.1.1.1 – Cyclosilicates; six-membered rings; beryl-cordierite group |
Strunz class # | VIII/E.12-10 – Silicates; cyclosilicates, six rings [Si6O18]12-; beryl series |