Senaite
Pb(Ti,Fe,Mn)₂₁O₃₈

     Senaite, a member of the crichtonite group, is extremely rare at Mont Saint-Hilaire.

PHYSICAL CHARACTERISTICS:

Color is usually black.
Luster is submetallic.
Diaphaneity is opaque.
Crystal System is hexagonal; R3.
Crystal Habits include sharp equant crystals to 1mm forming cyclic
   twins (trillings).
Cleavage not observed.
Fracture is conchoidal.
Hardness is 6.
Specific Gravity is approximately 5.3 g/cm³.
Streak is black.
Associated Minerals include aegirine, albite, catapleiite and microcline.
Distinguishing Features: Crystal habit (trillings).
Origin: Named in 1898 after Joaquim Candido da Costa Sena
   (1852-1919), Brazilian professor of mineralogy.

CLASSIFICATION:

REFERENCES:
MinRec 21:334-335 (1990), Dana 8:366 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

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