Nahpoite
Na2HPO4

     Nahpoite is extremely rare at MSH. It is difficult to distinguish from dorfmanite, halite, thermonatrite or trona.

PHYSICAL CHARACTERISTICS:

Color is usually white.
Luster is earthy.
Diaphaneity is opaque.
Crystal System is monoclinic; P21/m or P21.
Crystal Habits include powdery masses.
Cleavage (??).
Fracture is (??).
Hardness is (??).
Specific Gravity is approximately 2.6 g/cm3.
Streak is white.
Associated Minerals include aegirine, eudialyte, dorfmanite,
   natrolite, pectolite, quartz, sodalite and villiaumite.
Distinguishing Features: none from other powdery material.
Origin: Named in 1981 for its composition: sodium, hydrogen,
   phosphorus and oxygen (Na+H+P+O+ite).

CLASSIFICATION:

Dana System
# 37.1.5.1

Strunz Classification
# VII/A.03-10

REFERENCES:
MinRec 21:324 (1990), Dana 8:699 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

MSH
¤¤¤

PE
--

AP
--

MX
--

SS
--

MC
--

HF
--

BR
--

SX
¤¤

FR
--

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