Mold-blowing was an alternative glassblowing method that came after the invention of free-blowing, during the first part of the second quarter. A glob of molten glass is placed on the end of the blowpipe, and is then inflated into a wooden or metal carved mold. In that way, the shape and the texture of the bubble of glass is determined by the design on the interior of the mold rather than the skill of the glassworker.
Two types of molds, namely single-piece mold and multi-piece mold, are frequently used to produce mold-blown vessels. The former allows the finished glass object to be removed in one movement by pulling it upwards from the single-piece mold and is largely employed to produce tableware and utilitarian vessels for storage and transportation.Whereas the latter is made in multi-paneled mold segments that join together, thus permitting the development of more sophisticated surface modeling, texture and design.