If less spectacular to look at than the minerals on display, many of those additional hundreds are highly significant from a scientific and/or historic vantgage point. Included are dozens of the only known examples of their species to document occurrences named at scores of localities mentioned in the Society's 1940 publication Minerals of Maryland. Often the labels credit one the co-authors, Charles Ostrander or Willaim Price, with the finds. Two particularly interesting pieces are gem minerals.
The only reference to topaz in Minerals of Maryland is from Alto Dale Farm, which covered several acres at the southeast corner of Reisterstown Road and Cradock Lane in Baltimore County. Houses have completely covered the site for decades. The description noted "white cleavage masses" with quartz crystals" in "soil weathered from a pegmatite dike." The one pictured is the more impressive of two owned by the NHSM. They could well be the only known Maryland-collected topaz specimens in existence.
Another remarkable gem mineral
is the chrome tourmaline at right. It is from the Etchison Chrome Mine in
Montgomery County. Minerals of Maryland credits this find
to the late mineralogist Earl Shannon (1895-1961). It describes the mine circa
1940 as "not been worked for many years, and little of interest
remains at the site." The owner was Baltimore's legendary chromium mogul Isaac Tyson, who
also owned the operations at Soldiers Delight, Bare Hills and others extending
northeast into Lancaster County, Pennsylvania. Heyl and Pearre later reported
chrome tourmaline from the Line Pits, Rock Spring, Maryland. That find,
however, lacked the color and luster of the Etchison specimen, Moreover, it is
possible that the Rock Spring chrome tourmaline originated in underground workings on the
Pennsylvania side of the State Line. Much that was mined there
ended up on Maryland bases pits.
Topaz and chrome tourmaline are but two specimens out of nearly 50 NHSM pieces begging to be photographed as well as subject matter for stories.
It would be interesting to make a modern analysis of the "chrome tourmaline" and determine the species. Chromium-dravite? Chromo-aluminopovondraite?
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