Senior Moving Specialists: Mold lines in glass, Do they mean anything?

I often hear that if glass has 3 seems or mold lines that it’s old or antique. Like most old wives tales that misconception was based on a small amount of information that was not understood correctly. The mold lines or seems in glass have nothing to do with the age of the glass. Most glass, except entirely free hand or off hand art glass, is made with some type of mold or form. The lines in the glass are just the number of parts the mold is made of. Some intricate designs may require a mold to be made of several parts in order for the glass to be removed from the mold with the design intact. Simpler designs may only require a 2 part mold rather than a 6 part mold. The number of parts of a mold has nothing to do with age.

So where did that wives tale come from? There is a type of antique glass that uses the number of mold lines as part of the description of the glass. This is “Three Mold Glass” and refers to a specific type of glass made during a specific time period. It doesn’t mean all glass with 3 mold lines is antique. Three Mold Glass, 3 section mold blown glass, was produced in quantity starting around 1825. The 3 mold process was different than the other glass made at this time period which is one of the reasons why this type of glass was named “Three Mold Glass”. The other types of glass from this time period were hand blown and cut glass that showed no mold lines. The Three Mold Glass had a molded pattern that was cut into the mold itself, not into the glass after it came out of the mold. The patterns fell under different style categories: Geometric, Arched and Baroque. Most glass with 3 mold line is not Three Mold Glass. It has to be a particular style of glass made during the 19th Century.

When are the mold lines important? There are some patterns of glass that more than one company made. Sometimes a collector can tell which company made the item by the number of mold lines in the glass or where the mold lines are positioned on the pattern. For example, both Fenton and Anchor Hocking made hobnail cologne bottles for Wrisley. The bottles look identical but the companies used different molds. Fenton bottles were made with a 6 part mold, 6 mold lines. Anchor Hocking bottles were made with a 4 part mold, 4 mold lines. Another example, in the 1920’s many companies made nearly identical covered candy dishes particularly in Stretch Glass. On the 1 lb and ½ lb covered candy jars made by Fenton the mold line will be to the left of the narrow panel on the base. Northwood the mold line is on the right of the narrow panel on the base. There are other styles of covered candy jars where the details can also be used to determine which company made the item. This is where examining the mold lines is important. Otherwise mold lines aren’t very important in dating or identifying glass.

Cindy Danielski, Senior Moving Specialists on Ruby Lane & Ruby Plaza

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