One early method of decorating blown vessels was by applying random fragments of colored glass to produce a speckled effect. This was achieved by reheating the partly formed vessel and either rolling it in loose fragments or dropping the fragments onto it. The glassmaker could then reheat it and roll it on a marver (in Roman times, probably a stone slab) until the fragments were flush. Further inflation would enlarge and distort the flattened fragments, giving the glass a multicolored appearance. This may have been an inexpensive means of imitating costly mosaic glass. Glass with a speckled surface seems to have been a specialty of northern Italian glasshouses in the first century A.D. The jar shown here was decorated by gathering molten glass on the blowpipe, rolling it in chips of colored glass, and blowing the glass to the desired size and shape.