[meteorite-list] Why Fossil?

[Chauncey Walden]

Dean, since the loose definition of "fossil" is any evidence of former 
life, obviously a meteorite, well, most;-), cannot be a fossil. Paleo, 
or "old", is the better term, and in the case in discussion represents a 
meteorite that has fallen in past times to the extent of having been 
incorporated into what became a geologic formation and, in some cases, 
weathered out again. Your confusion seems to be between fossilization, 
or the preservation of any evidence of former life (like a basically 
unaltered mammoth tusk in the Artic), and petrification, or the 
replacement or pereservation of material by the introduction of silica, 
like petrified wood. The interesting thing, is that in well preserved 
petrified wood the cellulose can remain. The silica can be dissolved out 
and the cellulose structure captured and studied, even to the extent of 
taking biologic stains.