Dorfmanite

NaHPO · 2H

Dorfmanite is a very rare occurrence at Mont Saint-Hilaire. It is undistinguishable from other powdery white species such as brockite, cerussite, kaolinite, montmorillonite, nahpoite, natrophosphate, szomolnokite, thermonatrite and trona.

PHYSICAL CHARACTERISTICS:

Color is usually white.
Luster is vitreous to earthy.
Diaphaneity is translucent.
Crystal System is orthorhombic; (??).
Crystal Habits include powdery fillings and compact blobs.
Cleavage none apparent.
Fracture is (??).
Hardness is 1 – 1.5
Specific Gravity is approximately 2.0 g/cm
Streak is white.
Associated Minerals include aegirine, eudialyte, lovozerite, nahpoite,
natrolite, pectolite, quartz, sodalite, ussingite and villiaumite.
Distinguishing Features: none from other white powders at MSH.
Origin: Named in 1980 after Moisei Davydovich Dorfman (b. 1908),
prominent Russian mineralogist, who first reported the existence
of a sodium phosphate in 1963.

CLASSIFICATION:

Dana System
# 39.1.8.1

Strunz Classification
# VII/C.22-10

REFERENCES:
MinRec 21:306 (1990), Dana 8:738 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
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