I've been seeing a lot of beads with this same surface finish on eBay - new beads (India or Java?) treated by acid or tumbling or both, to look like they have aged. Not very convincing IMHO.
See recent examples on eBay:
183326450522
183326450525
352405694729
These are repros of Venetian trade beads. The seller is mis-representing them as originals. Probably what you were told also.