According to the consensus amongst the "scientific" community, the 1908 Siberian bolide was a meteor, not a comet, but the discussion about just what exactly it was is still being debated. Examine the much higher percentage of scientists that refer to it as a meteor in the journal list kept by the International Meteor Association
www.imo.net/bib/mtitun0.html
Comets normally consist of consists chiefly of ammonia, methane, carbon dioxide, and water, and wouldn't have produced such a large explosion at that altitude: but there were iron and nickel fragments found.
"Sekanina admits the question is still open. "I tell you quite frankly that
there is a lot of handwaving in this. There isn't any quantitative theory
available that would give you so many tons of material at such and such a
height above the Earth's surface." Nevertheless, he is quick to add, the old
comet-tail hypothesis is untenable. Even the dustiest tail would not
contribute enough material to cause the glows seen.
While the finest particles drifted westward from Tunguska, some of the
vaporized remains of the meteorite condensed into particles a fraction of a
millimeter in size. They rained onto the devastated terrain, and microscopic
spheres of metal and glass were painstakingly sifted from the soil by
expeditions during the late 1950s and early 1960s. Lest there be any doubt of
their extraterrestial nature, Soviet researchers soon found abnormal
concentrations of nickel in the samples, indicative of meteoritic origin."
www.totse.com/en/technology/space_astronomy_nasa/tungusk2.html
"In 1993 researchers Chris Chyba, Paul Thomas, and Kevin Zahnle studied the Siberian explosion and concluded it was of this type -- a stone meteorite that exploded in the atmosphere. This conclusion was supported when Russian researchers found tiny stoney particles embedded in the trees at the collision site, matching the composition of common stone meteorites. The original asteroid fragment may have been roughly 50-60 meters (50-60 yards) in diameter."
www.psi.edu/projects/siberia/siberia.html
You really are a very argumentatively-prone opinionated person.