Reederite-(Y) (Type Locality)
(Na,Mn,Fe)₁₅(Y,REE)₂(CO₃)₉(SO₃F)Cl

     Reederite-(Y), formerly UK # 102, is extremely rare at MSH. Only a few milligrams are known to exist.

PHYSICAL CHARACTERISTICS:

Color is usually yellow to orange-brown.
Luster is vitreous.
Diaphaneity is transparent to translucent.
Crystal System is hexagonal; P6.
Crystal Habits include blocky grains to 2mm.
Cleavage {001} is perfect.
Fracture is conchoidal.
Hardness is 3 - 3.5
Specific Gravity is approximately 2.85 g/cm³.
Streak is white.
Associated Minerals include analcime, catapleiite, manganotychite,
   petersenite, shortite and trona.
Distinguishing Features: Crystal habit and color.
Origin: Named in 1995 after Richard J. Reeder, American professor
   of Geology.

CLASSIFICATION:

REFERENCES:
AmMin 80:1059-1064 (1995)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

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