However, inspiration struck Zlobin. Why not look for meteorites in nature's very own rock-sorting machine? While collecting small rocks from the Khushmo River's sediment, he came across several fragments possibly from the Tunguska fireball. In total, 100 samples were collected.
"In 2008 the author sorted his collection of stones from the Khushmo River's shoal and selected three stones with traces of melting, which were described and officially registered," Zlobin writes in a paper published on the arXiv preprint service.
He noted that the three stones from the 100 samples - measuring between 20-30 millimeters - exhibit signs of atmospheric melting and surface structures that appear to be regmaglypts - indentations synonymous with meteorites, caused by vortices of hot atmospheric gas digging out small pockets of material. There also appear to be "shatter cones" in the mix, geological samples that exhibit signs of a huge impact.
NEWS: Antarctica's Tunguska Event
One of the three meteorite candidates, a glassy sample Zlobin calls "Dental Crown," contains bubbles and appears to have undergone plastic deformation - a factor, by Zlobin's reckoning, that was caused by the immense temperatures produced in the atmosphere. Also, the presence of a glassy meteorite candidate (containing bubbles) appears to back-up a similar glassy sample recovered from Tunguska during the L. A. Kulik expedition in the 1930′s. That sample, however, has since been lost, making a direct comparison impossible.