Fulgurites
Over 800 specimens comprise this lot and they will all be sold together as a single unit. They include the largest known grouping of exogenic fulgurites, as well as an enormous lot of ground fulgurite all created at the same lightning strike in New York State. It is hoped that these specimens would be used to create the first known museum display on exogenic fulgurites, but it is understood that the institution acquiring the lot will use or dispose of the specimens as they see fit.
Background
The strike which produced all of these fulgurite specimens occurred on August 2nd, 2008. The strike occurred at 43°27’39.65” N latitude by 76°30’2.22” W longitude between the roadway and sidewalk on 100 East Cayuga Street at an elevation of 88.4 meters above sea level. This is approximately six city blocks from the southeastern edge of Lake Ontario. The site was composed of four distinct impact spots. The entire strike site was approximately five meters in length and two meters in width. A paper documenting the occurrence and describing its scientific significance is in press with Rocks and Minerals magazine.
The Oswego, New York, exogenic fulgurite occurrence represents only the second occurrence of these unusual fulgurites to be documented, the first being the Elko, Nevada, occurrence, found in 1997 (Mohling, J. W. 2004. Exogenic fulgurites from Elko County, Nevada: A new class of fulgurites associated with large soil-gravel fulgurite tubes. Rocks & Minerals LXXIX: 334-40). Many similarities between the strikes exist, but it is the differences that are of interest. Further, this strike was found and excavated only days after its discovery vs. years after its discovery which seems to be the case in the Elko example.
Exogenic fulgurites of all forms and combinations of forms were present on the surface of the ground surrounding the impact points of the lightning. They extended outward for an estimated radius of no more than a meter. Filaments with and without attached droplets were found to 13 cm in length. Individual and small groupings of this form were some of the most aesthetic specimens recovered from the find. A few of these were larger aggregates. Spinose and flagellated varieties of droplets, were relatively common as were small droplets that were roughly spherical. The droplets were mostly green in color and ranged in size from 1 mm to 3.5 cm. About a third of these specimens are completely hollow, with no external openings, and they float in water. Microscopic investigation showed that even the smallest droplets and spheres to be highly vesicular having between 20 and 70 percent open space. Less common were clusters of these droplets or clusters connected by filaments. Drapery like forms or sheets of material were also found beside, and attached to, ground fulgurites.
The surfaces of the exogenic fulgurites vary in texture. Those that appear to have solidified in the air have smooth, lustrous surfaces on all sides. Most, however, appear to have only been partially solidified upon their impact with the ground, with one side being smooth and lustrous and the opposing side having a texture reflecting the soil surface, sometimes with small bits of soil attached. The assemblage of colors in order of decreasing frequency of occurrence are: (1) green; (2) gray to black; (3) white; (4) silver; and (5) brown.
Photographed above, and below are some examples of the exogenic fulgurites (to 13 cm each) and photographs of the 8 boxes (click to enlarge) of specimens fitting this description. The boxes in which they are photographed measure approximately 40 x 20 centimeters...
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The recovered tubes reached diameters to 30 cm but were seldom any longer than this because the very compact nature of the soil made their removal in longer sections difficult. These were larger in diameter than fulgurites from most other locations. However, they were typical in form to those from other locations, possessing central vesicular glass tubes with coarse exteriors composed of partially melted and loosely attached soil and accessories. Because of the soil’s high content of “junk” accessories, these fulgurites had a diversity of materials incorporated, fully melted, into their interiors, and attached, partially melted, to their exteriors. At the easternmost impact and one of the central impact spots the fulgurites reached and fused into the sidewalk. Minor fusion crusts formed on the surface of the sidewalk in those areas as shown in the westernmost peripheral impact.
Color variations and banding was evident in many of the exogenic and ground fulgurite specimens. When examined closely, some of the gray and black exogenic fulgurites can be seen to range from dark gray to black within the same specimen. The lighter-colored specimens, mostly those of a green color, show more dramatic color variations and banding within a single specimen.
Photographed below are the 14 boxes of ground fulgurite specimens. There are a total of 21 boxes of specimens in this lot and the boxes in which they are photographed measure approximately 40 x 20 centimeters...
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All the specimens collected are being sold in this lot. The only specimens withheld are several kept as souvenirs by the individual who found the majority of them and several which I will retain that are photographed for the article in press.
The lot price will be provide upon request. mwalter@twcny.rr.com
Thank you for your consideration.
