Maryland Wulfenite

We print this article here as I wrote it for the Spring, 2011 edition of Justin Zzyzx's quarterly publication the Vug, which is also available in print with this addition entirely devoted to the mineralogy of Maryland. Both sites are in the public domain, so posting it here as well should help to create the awareness of Maryland's minerals sought by both publications.

Though little recognized for its wealth of approximately 250 mineral species, the state of Maryland boasts its share of mineralogical anachronisms. One of the most interesting is a singular and unique find of wulfenite from the year 1975 at a Lehigh Cement Company owned crushed stone quarry near Union Bridge in Carroll County. Extracting from the Wakefield Marble of Maryland’s piedmont, the quarry remains open today, its operations much expanded. For many years, it has been totally off limits to any and all collectors.

Maryland wulfenite’s bright yellow colour visually distinguishes it from the better known East Coast wulfenites, namely the reddish orange crystals of former lead producing sites near Phoenixville, Pennsylvania, and the orange crystals from the Pre-Revolutionary Manham lead workings at Loudville, Massachusetts.

Drusy colourless and sometimes-yellow stained calcite nearly always accompanies Maryland’s usually tabular tetragonal wulfenite wulfenite crystals. Though visible to the naked eye, they rarely measure more than a few millimeters, the largest known being about a centimeter in length. Nearly always, they are best appreciated with magnification. Similarly sized colourless crystals of cerussite frequently accompany them.

The late George Brewer, a schoolteacher from Columbia, Maryland, discovered and extracted all of Maryland’s known wulfenite bearing material. Since meeting an untimely death about 30 years ago, his name has become legend to seasoned field collectors in the region. They recall that he usually collected alone during the summers when school was not in session.

John S. White, who was Curator in Charge of the Smithsonian’s National Museum of Natural History Division of Mineralogy from 1964 to 1991, had more to say:

I knew George very well. When I lived in Bowie, he used to come often to my home and show me things that he had collected, or just to visit and talk about minerals. In my view he was the best collector in the state of Maryland that I have ever known. He was always turning up amazing things and he had a knack for gaining official access to quarries where collecting was prohibited. He probably found more new species for quarries in the area than any other collector, and he also found several species new to the science. I am sure there would have been a mineral named for him if he had not died at such an early age. Perhaps the most exciting discovery that George made was that of the mineral goosecreekite. He found the very first specimen at the Goose Creek quarry in Loudon County, suspected that it was a new species, and it turned out to be just that. It was subsequently named and described in 1980 using the material that he collected (Dunn, et. al, Canadian Mineralogist, vol. 18, pp. 323-327).

Word has it among the relatively few who are even cognizant of Maryland wulfenite that every known specimen was once part of single rock. August “Andy” Dietz, an Ashland, Virginia dealer and collector who acquired from Brewer several flats of wulfenite bearing material, adds perspective: He recalls:

From what George implied about the wulfenites, they were in an exposed seam in a corner of the quarry that was probably three to four feet long and a couple offeet wide. George was only able to extract what was loose from the blast but he seemed to think he got all that was available to get. The next time he went he
said the area had been blasted away.

Brewer never found any more. Nor did Dietz, when he later collected there with the renowned Maryland collector Fred Parker. For sure this crushed stone quarry at Union Bridge is not typical of a locality where wulfenite would be likely to occur. Nor is any other locality in the state. The Union Bridge wulfenites are a scarce anachronism to be considered a Maryland classic.