Unless otherwise noted, all photographs by the author of specimens in his collection
When lightning strikes the earth's surface and melts the materials it contacts, the remains are collectively known as fulgurites. Their classification has generally been limited to forms that include self-descriptive titles such as ground or soil fulgurites, sand fulgurites, rock fulgurites, and clay fulgurites (Galliot 1980; Petty 1936). All of these classes of fulgurites form at or below the surface of the ground. In 2004, Mohling published the first documentation of exogenic fulgurites produced from a lightning strike. This new class of fulgurites was described as liquefied materials resulting from a powerful lightning strike that were thrown into the atmosphere above the lightnin's point of impact and solidified in the air. This unusual occurrence is located in the Elko Hills of northeastern Nevada just south of the town of Elko. Here I document a second such occurrence, which was discovered in the city of Oswego, New York, on 2 August 2008. The information that follows should add further insight into the nature of this rare phenomenon.
On 9 August 2008 Jeffrey Shallit approached me at the East Coast Gem, Mineral, and Fossil Show in West Springfield, Massachusetts, with an offer to sell fulgurites he, his sons, and nephew had dug from a lightning strike site in Oswego, New York, the day before. The strike had occurred seven days prior two short blocks from his nephew's home on a residential side street in downtown Oswego. He had a handful of specimens, several of which I recognized as being exogenic in nature. After reviewing the several boxes of specimens he had in his car, I purchased the entire lot, excluding only several he wished to keep as souvenirs.
Michael Walter is an earth science and geology teacher and an active field collector of the minerals of upstate New York and Canada.