Sphalerite

Unknown Owner

Superb for this locality and species, large lustrous twinned crystals of sphalerite in a cluster without matrix. Crystallized completely all around. About as good as it gets from here for this noted locality for the species. This is in super condition all around.The Plum Run Quarry, located near Peebles in Adams County, Ohio, is a massive limestone and dolomite operation set within the geologic framework of the Cincinnati Arch. Geologically, the quarry exposes a significant section of Silurian-aged strata, primarily the Peebles Dolomite and the Lilley Formation, which represent ancient carbonate reef environments. These units are characterized by a porous structure that hosts vugs containing minerals such as calcite, pyrite, and quartz. Most notably, the locality is famous among collectors for its sphalerite, which typically occurs as dark, lustrous crystals nestled within the rocky cavities. Historically, the quarry has been an essential regional source of crushed stone, agricultural lime, and industrial aggregate for over a century, with large-scale operations under various owners, including Davon Inc. and later the Martin Marietta company, spanning from the early 1900s through to the present day. While primarily an industrial resource, the locality remains a classic Ohio mineral site due to the high quality of the sphalerite specimens recovered during excavation.