Fluoro-richterite
Wilberforce area, Monmouth Township, Highlands East Township, Haliburton County, Ontario, Canada
11.8 x 6.8 x 4.7 cm. Nestled in a matrix of ivory colored feldspar, probably nepheline, are several crystals of fluororichterite, the largest of which is doubly terminated, black with good luster, and measures 5.2 cm in length. Fluororichterite is a sodium calcium, magnesium, silicate, fluoride.
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