Within a brief period of time, using the flint glass formula, the pressed glass industry exploded into the feverish production of fancy patterned glassware. The first patent for machinery to produce press molded glass, or just вЂpressed glass,вЂ™ was granted in America in 1821. Blown-molded glass will have many of the same characteristics as press molded glass, with the additional trait of having indentations on the interior of a piece that correspond to the raised pattern on the outside surface.

This arrangement was a fairly time consuming process but allowed for the impression of elaborate patterns to be repeated on additional pieces more quickly than would have been possible if hand-cutting the design each time. A glob of molten glass was placed into a hinged mold and blown to fill it. In America, early molded pattern glass was originally blown-molded, which combined glass blowing techniques with that of pattern molding. Glass with a patterns molded into the surface has been made in the past in both the вЂflintвЂ™ and вЂnon-flintвЂ™ formulas, with the former almost invariably used in earlier molded pattern glass. RavenscroftвЂ™s formula produced вЂflint glassвЂ™ AKA lead crystal.

But neither if these two formulas could produce a glass as entirely suited for cutting and engraving as was a third glass formula containing oxide of lead developed by Englishman George Ravenscroft in 1676. The type of glass desired depended on the formula used to make it. Being aware of what those differences are can assist in sure and proper identification and help to prevent potentially costly mistakes being made, either when buying patterned glassware or offering it for sale.ДЇrom the very early beginnings of glass-making there were only two basic formulas for glass and these were fairly simple a silica (sand or quartz) was heated with an alkaline flux (potash or soda). There are indeed considerable differences between molded and cut patterns on glass.

This type of вЂidentificationвЂ™ seems to be a conventionally accepted practice, though it may cause someone to eventually give a buyer incorrect information. They will state that their description of a molded pattern as вЂcutвЂ™ is correct and base this perception on inaccurate glass nomenclature which may be found in many places elsewhere on the Internet. Fact Check: Cut Glass or Molded Pattern Glass?ДЄ common mistake new buyers and collectors of glass will sometimes make is to look at a piece of glass with a molded pattern and mistake it for glass onto which a pattern or design has been manually вЂcut.вЂ™ On occasion, too, if this error is brought to the attention of some dealers, they may even insist no misidentification has taken place.

Crystal maker marks