Britholite-(Ce) - [(Ce,REE,Ca,Na)5{(Si,P)O4}3(OH,F)] - Saint-Hilaire (original) (raw)

Britholite-(Ce) is an uncommon member of the apatite group at Mont Saint-Hilaire. It is very similar to several other species such as pectolite, cancrinite and revdite, and visual identification is impossible.

PHYSICAL CHARACTERISTICS:

• Color is usually colorless.
• Luster is adamantine.
• Diaphaneity is transparent to translucent, and opaque.
• Crystal System is hexagonal; _P_63/m or _P_63.
• Crystal Habits include radiating groups of prismatic crystals
  to 1.5mm long, tabular grains and anhedral grains.
• Cleavage none observed.
• Fracture is conchoidal to uneven.
• Hardness is approximately 5.
• Specific Gravity is > 3.9 g/cm3.
• Streak is brown.
• Associated Minerals include aegirine, analcime, astrophyllite,
  biotite, calcite, fluorite, monazite, pectolite, sodalite and zircon.
• Distinguishing Features: Crystal habit and luster.
• Origin: Named in 1901 from the Greek brithos, weight, alluding
  to its relatively high specific gravity.