I've read in my daily newspaper an incredible news: in Split there were found fragments of a sarcophagus, made of crimson porphyry, a very rare and precious material that only of the highest rank used, and many historians and archelogists think that are fragments of Diocletian's sarcophagus. Plus, they were found maybe a century ago, in a location near the Diocletian's palace, and they were safely stored in the Museum of Archeology.
Restaurators will try to put it in one piece, but it won't be returned to the mausoleum or substuctures. (they say ithose are not a cemetaries any more )