Allanite-(Ce)
(Ce,Y,Ca)₂(Fe²⁺,Fe³⁺)Al₂(SiO₄)(Si₂O₇(O)(OH)

     Allanite-(Ce) is extremely rare at MSH

PHYSICAL CHARACTERISTICS:

Color is usually beige to dark brown on the acicular crystals and
   varies from very deep red to dark brown on the tabular crystals..
Luster is vitreous on tabular crystals and dull to greasy on
   acicular crystals.
Diaphaneity is transparent to translucent on tabular crystals and
   opaque on acicular crystals.
Crystal System is monoclinic; P2₁/m.
Crystal Habits include sharp, thin tabular crystals to 4mm
   and aggregates of radiating individual crystals.
Cleavage: {001} is imperfect and {100}{110} are poor.
Fracture is conchoidal to uneven.
Hardness is 5.5 - 6.
Specific Gravity is approximately 4.11 g/cm³.
Streak is gray.
Associated Minerals include calcite, chlorite group, dolomite and
   quartz.
Distinguishing Features: Crystal habit and color.
Origin: Named in 1810 after Thomas Allan (1777-1833), the Scottish
   mineralogist who first noticed it.

CLASSIFICATION:

REFERENCES:
MinRec 21:294 (1990), Dana 8:1196-1197 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

Legend