I had this too, but after the initial heart attack it turned out to be "just" swarf, probably from the gears.
The chrome coming off the rockers is very distinctive and it's little patches of very thin silvery metal, compared to the chippings of swarf that come off the metal.
Guido had a really nice pic, but it's not in the thread any more...
http://ducatisportingclub.com/contro...d.php?tid=3893