Saturday, March 13, 2010

Different Pokrovskite Habits, a Possible New Mineral, Hunting Hill Closed

Despite a 1987 article by John White in Mineralogical Record entitled "Pokrovskite: A Common Mineral" ---pokrovskite is by all accounts relatively obscure. MINDAT currently shows only three images of this magnesium bearing carbonate of the rosasite series and names but seven localities around the world from which it's been reported. Perhaps MINDAT will show more images after I submit two of my own, but we'll have to see. They will differ visually not only from each other, but from all three of the images presently up on MINDAT. One is the micro-photograph at the right end of the above full view, macro, micro progression. The other will be the image at right of pokrovskite bearing a more unusual "satin spar" habit.

During my visit this past December to discuss and photograph Maryland Minerals at the Harvard Mineralogical Museum, its curator Carl Francis more than once mentioned pokrovskite as an example of one of the relatively few rare minerals known to be found in Maryland. He made a point of showing me the Museum's premier specimen with the familiar brown radiating tufts. Later, as I observed and photographed Harvard's Maryland micromounts, the "satin spar" piece turned up. Quite deliberately albeit incorrectly, I referred to the pokrovskite identification as "questionable" in a caption beneath the photograph.

No sooner had I mailed the image (and caption) as part of a "Harvard's Maryland Minerals" CD to Dr. Francis than Fred Parker, who authored "The Minerals of Hunting Hill Quarry, Rockville Maryland," in the September, 2005 Mineralogical Record, replied to a recent Email from me requesting his opinion regarding the pokrovskite identification. "Maybe," Fred wrote."One form of pokrovskite is a 'satin spar' like formation which this resembles." Later in day, once I'd informed Parker that Harvard had obtained the micromount specimen from Fred Shaefermeyer, his response was: "Absolutely. Fred Schaefermeyer was the Prince of Pokrovskite."

Fred Parker and the much older Fred Schaefermeyer were close friends who collected together at Hunting Hill before and through the 1990's. In addition to dubbing Schaefermeyer the "Prince of Pokrovskite,"Parker also spoke of him as the "father of Hunting Hill micromineralogy, a cheerful and intelligent man whose forte was a an eye for picking up minerals that looked different." After his eyesight had declined to the point he could not longer collect, Schaefermeyer dissipated his collection and turned over to Parker several flats of unlabeled Hunting Hill minerals.

Parker sent several pieces about which he was particularly curious for analysis at James Madison University by Lance Kearns. One was the "satin spar" like material, which Kearns identified as pokrovskite. He also uncovered another brown and radiating mineral from the rosasite series that he could not identify. The possibility seems realistic that this could be a new mineral. To date, no one has come forward to probe further regarding its possible submission to the IMA for approval as such.

And now for the bad news: Prospects have been quashed at Hunting Hill for collecting any more pokrovskite, any more of this potential new mineral, or for that matter any of the 70 species known to occur there. A Swiss company recently purchased Hunting Hill and closed it to all with interest in collecting.


  1. With the recent addition of Omphacite, there are 70 known species at Hunting Hill.
    Fred Parker