Pyrrhotite
Fe_1-xS(x=0-0.2)

     Pyrrhotite is a fairly common sulfide at Mont Saint-Hilaire. The -4C polytype is monoclinic. Large crystals that appear to be pyrrhotite are usually hexagonal pseudomorphs of pyrite after pyrrhotite.

PHYSICAL CHARACTERISTICS:

Color is usually bronze-yellow.
Luster is metallic.
Diaphaneity is opaque.
Crystal System is monoclinic; A2/a.
Crystal Habits include sharp tabular to short prismatic pseudo-hexagonal
   crystals to 1.5cm and as masses.
Cleavage none observed.
Fracture is conchoidal to uneven.
Hardness is 3.4 - 4.5
Specific Gravity is approximately 4.6 g/cm³.
Streak is grayish-black.
Associated Minerals include aegirine, albite, analcime, biotite, brookite,
   calcite, dolomite, ilmenite, natrolite, quartz, riebeckite, siderite,
   synchysite and titanite.
Distinguishing Features: Crystal habit.
Origin: Named in 1835 from the Greek pyrrotes, reddish, in reference
   to its faint reddish color.

CLASSIFICATION:

REFERENCES:
MinRec 21:331 (1990), Dana 8:74-75 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

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