> the fingerprint method has now also been submitted for patenting and taken up by a medical technology company
So simple — why hasn't anyone thought of that already?
typically you don’t know that you are looking for steel-balls in sand, you might be looking for gold coins etc. in such cases the space of all interesting fingerprints is just too large.
The interesting fingerprints are the ones which are different than the surrounding material.
And that is too large a space to test them all with this method.