Pressed glass is actually molded glass, since it was made by pressing molten glass into a mold either by hand or by machine.
Heisey, among other companies that made fine quality glassware, employed hand pressing to produce elegant glassware entirely by hand. Evidence of the mold is rarely seen on these pieces.
Examples of machine-pressed glass would include most Depression glass patterns, and many times mold lines are quite visibly present on these lower quality pieces.
How was Pressed Glass Finished?
Collectible pieces of both hand- and machine-pressed glass were often finished by a method called fire polishing by elegant glass companies. This technique required applying a direct flame to give fire polished (a term often used in marketing glassware when it was new) pieces an even, glossy finish. This finishing process is sometimes referred to as glazing as well. Pieces with a more uneven texture and less of a gleam to the finish were not fire polished.
Why is Pattern Glass Sometimes Described as Pressed Glass?
Sometimes the term pressed glass is used generically by antiques dealers and novice collectors to describe pattern glass. While this type of glass is a form of pressed glass due to the way it was manufactured, the terms used by avid collectors to describe it are Early American Pattern Glass or simply pattern glass.
Early American Pattern Glass (EAPG) was made using molds of one or more parts depending on the size of the piece being made, and molten glass was pressed into the molds. The molds could be quite intricate when used to produce figural knobs and patterns featuring animals, fruit and other elaborate motifs. Like Depression glass (although EAPG dates largely to the late 1800s), these pieces were a part of everyday glassware sets when they were new and can contain mold marks, although some of the busier patterns hide them quite well.
Do Some Pressed Glass Pieces Look Similar to Cut Glass?
Yes, some pressed glass items mimic cut glass and were made as a cheaper alternative to their more labor intensive and costly counterpart. One company associated with this type of product is Imperial Glass Company. Imperial used the Nucut (pronounced “New Cut”) mark on many of its pressed glass pieces that simulate cut glass. But when examined in comparison, the “cuts” on pressed glass pieces do not have the sharp feel to them found when running a finger across a piece of cut glass in the same manner you would employ if checking glassware for damage .