Zircon and Apatite, Pacoima Canyon CA

Pacoima Canyon in California is well known for its zircons. Less well known, these specimens also contain apatite. I was browsing my daughter's inventory (with MW) while in Florida a couple of weeks ago and found this piece in the Joe Daley inventory. It was simply labeled as zircon. But it was amazing under MW which revealed the bright apatite. I can't imagine how many "sleepers" there are in old collections simply labeled zircon.


Quote from George J. Neuerberg, U. S. Geological Survey, Pasadena, California.

Zircon crystals occur as doubly terminated square prisms that range in size from those barely visible with a hand lens to a known maximum of 1 inch by 8 inches. Despite the intense fracturing, no evidence of alteration or metamictization is apparent. The color ranges, according to the extent of fracturing, from purplish white to deep purple. Under the shortwave ultraviolet lamp the crystals fluoresce a deep orange yellow with little variation in the intensity of the color.

Microscopic crystals of apatite are present in the pegmatite and in all of the surrounding rocks. Apatite is most abundant, and its crystals-stubby prisms up to 1/4 inch-are largest in association with ailanite and zircon, in both of which it is a common inclusion.



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