Sunday, June 6, 2010

Northern Virginia Then and Now

The two Centreville Quarry apophyllite on prehnite specimens at left are displayed at the Smithsonian. Those at right are from the collection of a Northern Virginia resident who has been prospecting in the area for more than half a century. While the pieces from the Smithsonian are better known, all are classics specimens from a classic locality. On Lee Highway less than 30 miles from the Smithsonian, the Centreville Quarry is home turf.

On a spur of the moment visit to Washington, D.C. last week, I had dropped by the Smithsonian while my wife accompanied her cousin, who was visiting from Texas, took in the Mall on a tour bus. The only minerals I took time to photograph were the two apophyllite and prehnite specimens at top left. My purpose was to show them to my friend Harold Levey, who in the good old days circa 1950 had permission to camp out at the Centreville quarry and scarf up such material to his heart's content. Harold and his buddies once showed up at the Smithsonian with a particularly attractive specimen and cut a deal with then Curator of Minerals George Switzer to exchange it for a duplicate mimetite specimen from its Robeling Collection. Their Centreville Quarry find quickly found a home in a prominent area of the mineral gallery, which in those days was in a different part of the Museum of Natural History Building. Needless to say, much has changed over 60 years both at the Smithsonian and the former mineral collecting environs of Northern Virginia.

As synchronicity would have it, two days later I found myself at the Falls Church home of the collector who owned the equally if not more impressive specimens pictured at top right. My original plan for that day had been to check out the site of a long forgotten 1960's gypsum find with Jeff Nagy for his project to update and revise the 1980 Maryland Geological Survey publication Minerals of the Washington, D.C. Area by Lawrence R. Bernstein. After those arrangements were postponed, Jeff had arranged instead for us to visit a source whom the original publication had credited with "oral communications" relating to several noteworthy Northern Virginia finds from quite far off the beaten track. He was also the owner of those other two classic apophyllites on prehnite.

While providing us with extensive input that was both timely and informative, he also shared fascinating details relating to the "outside the box" journey that led to his encyclopedic knowledge about the geology, mineralogy, paleontology, and archaeology of Northern Virginia as well as owning some of the finest mineral specimens the region ever produced. His request for anonymity helped me stay focused on the material at hand.

In addition to the apophyllite and prehnite specimens that I was able to photograph, his collection included the most spectacular stilbite crystals I've ever seen from Virginia as well as an amazing byssolite specimen needing to be seen to be believed. Like the apophyllites on prehnite, both of these specimens were also collected years ago at the Centreville Quarry. Since their locations in the cabinet were not conducive to photographs that would do them justice and because of time and space constraints, we agreed that they would be photographed on a subsequent visit.

Most of the collecting in Northern Virginia is now limited to those rare occasions when by special arrangement, a couple of quarries long past their collecting primes permit mineral societies to visit on field trips. Otherwise, little remains accessible beyond stream beds and their cobbles. Our host collected the ilmenite specimen at left, which is by far the largest specimen I've ever observed from the United States, from such a deposit just a few yards from Military Road. He also showed us no less impressive a treasure from another stream bed deposit in Holmes Run. It was a perfectly terminated and barely tumbled three inch by two inch amethyst crystal. We surmised that perhaps it had weathered relatively recently from a nearby matrix and probably become buried soon thereafter.

In coming weeks, Jeff Nagy will be prospecting such stream beds and what few other Northern Virginia collecting spots of which any trace remains. Once published, his revision of Minerals of the Washington, D.C. Area will bring its readers up to the moment.

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