(meteorobs) Earth Meteorites

[Pat]

We have meteorites from Mars and the moon...but it should be feasible that events such as Yucatan and Meteor crater - lead me to wonder if parts of Earth could have been blasted into space and return later as meteorites?
The question is would we recognize them as coming from Earth and would we be able to tell how long they were in space?

I know gamma ray alterations will allow us to tell how long it has been in space, but would it alter it such that we would not be able to tell it was originally from Earth? This may be a source for very old Earth rocks.