Watch Dr. Lori show you how to identify valuable cut glass using your fingers.
by Dr. Lori Verderame
Cut glass dates back to ancient Egypt (1500 BC) and the popularity of the objects sparked an interest in glass cutting in Rome, the Middle East, Turkey, Venice and the rest of Europe. Glass objects were cut with metal drills, and later with stone wheels. The use of various sizes of cutting wheels produced a pattern in the glass.
American Cut Glass
In America, about the time of the Revolutionary War, the American Flint Glass Manufactory was established in Manheim, Lancaster County, Pennsylvania. Here, the first cut glass in America was produced. When determining the dates of cut glass, the period from 1771 to 1876 is considered the early period of American cut glass. From 1876 or the time when the Centennial Expo was held in Philadelphia to circa 1914, cut glass was characterized as Brilliant glass.
Circa 1876, high quality silica deposits were found in the US which sparked innovations in glass making formulas. Shortly thereafter, electricity and the discovery of natural gas changed the way cut glass was made. Steam powered cutting wheels were replaced with more accurate electric ones. And, natural gas glass furnaces made it easier to control the temperature levels used during the glass making process. Glass furnace temperatures were controlled and glass cutting machines were improved and thus, the product of cut glass was better.
American Brilliant Cut Glass
While glass was viewed as inexpensive, there were high labor costs and the need for skilled craftsmen to make a piece of cut glass. Cut glass soon became a luxury item. While Europe had previously cornered the market on beautiful cut glass pieces, by the time of the 1876 Centennial Expo and the fabulous cut glass objects on display there were introduced, it was obvious that quality cut glassware had arrived in America. The robber barons of the Gilded Age in America—the Vanderbilts, the Carnegies, the Morgans—proudly displayed American Brilliant cut glass in their mansion homes. American brilliant glass was collected by U.S. Presidents, Edward VII of Great Britain, politicians, industrialists, celebrities, etc.
Makers of Cut Glass
Some of the most famous producers of American brilliant cut glass were: T.G. Hawkes, Steuben (T.G. Hawkes with Frederick Carder), Libbey, Dorflinger, Egginton, and Meriden, among others.
During the Brilliant Period nearly 1,000 glass cutting shops were in business, but by 1910, fewer than 100 remained in business. During World War I, the lead oxide used in the production of glassmaking was needed for the war effort. Glass for cutting requires 40% lead oxide. The lead oxide changes the properties of the glass. Lead oxide softens the existing glass in order to allow the cutting wheels to produce patterns without shattering the glass. The glass mixture is made up of silica, potash, and lead oxide. This was melted in a furnace at 2400 degrees F and blown into the desired shape or form. Glass was shaped and placed into an annealing or cooling oven where it was allowed to cool to room temperature. Some pieces of glass could take as long as 10 days to cool in order to then be cut. If the piece was cut before it was fully cooled, it could shatter and break.
A glass cutter, called a “rougher”, would hold the piece of glass against a fast moving, beveled, metal wheel. While cutting, the glass piece would be cooled and the cut depth would be determined by the expertise of the rougher and the sound of the wheel. Many wheels would be employed to cut a design. A smoother would finely cut the designs and a polisher would polish each cut using wooden wheels or acid and a perfect piece would be the result.
American cut glass is a very valuable collectible on the antiques market. Values range based on quality, maker, condition, and pattern and many pieces regularly are worth $1,000 to $100,000.
Get an online appraisal of your piece of glass from Dr. Lori.
Dr. Lori also discusses pressed glass pieces.