Brockite
(Ca,Th,REE)(PO₄) · H₂O

     Brockite is an extremely rare species at Mont Saint-Hilaire. It is an unattractive phosphate, member of the rhabdophane group.

PHYSICAL CHARACTERISTICS:

Color is usually white.
Luster is earthy.
Diaphaneity is opaque.
Crystal System is hexagonal; P6₂22.
Crystal Habits include white powdery masses to 8mm.
Cleavage not observed.
Fracture is conchoidal.
Hardness is 3 - 4.
Specific Gravity is approximately 3.9 g/cm³.
Streak is white.
Associated Minerals include aegirine, analcime, epididymite,
   eudialyte, leifite, mangan-neptunite, natrolite, nenadkevichite,
   polylithionite, sérandite, steacyite and yofortierite.
Distinguishing Features: None evident..
Origin: Named in 1962 for Maurice R. Brock, geologist, U.S.
   Geological Survey, who found the first specimens.

CLASSIFICATION:

REFERENCES:
MinRec 21:299-300 (1990), Dana 8:808 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

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