Collecting the Tools of the Trade: Glass Molds

Collecting the Tools of the Trade: Glass Molds

Exploring Antique Technologies
by Kary Pardy

Every object holds clues as to how it was made, with some being more obvious than others. Since you are reading this issue, chances are good that you have run your fingers along a telltale ridge in a piece of glassware, or could find one amongst your collection right now. Molded glass emerged onto the scene as a cheaper alternative to popular, pricey cut glass or crystal, and now holds a place in our hearts in its own right. But what about the tools that made all of this possible? Lets take a closer look at glass molds and whether or not there is a market for these tools of the trade.

Blown Molded Glass

First, let’s clear a few things up. “Pressed” glass is essentially also “molded” glass, but the terms are not always talking about the same thing. The mold is the common factor through the years, and Byzantine, Roman, and Islamic craftsmen were all inserting hot glass into molds to create decorative pieces. American glass enthusiasts, however, first start getting excited about “blown molded” glass in the early 19th century, as this ancient technique gained traction following the War of 1812 as a cheaper substitute for the fancy cut glass coming out of Waterford, Ireland. Instead of an artisan chiseling away at individual pieces, a glassblower would blow glass directly into a mold to create a desired pattern. These pieces will bear both the marks of a mold and a pontil.



The molds themselves were typically cast in bronze or iron, and were made all across the United States and Europe by professional mold manufacturers. The most common style had three parts that hinged open and would have revealed designs on all sides. The artisan would blow glass into the mold until glass fitted into all of the mold’s interior grooves and then would open the mold with a hand or foot pedal. From there, more blowing and shaping would finish the piece until it was cracked off from the initial rod, creating the signature pontil of blown glass.

Molds impressed a pattern, but it was up to the glassblower to shape it. A straight ribbed mold could be used to create a swirled handle, for example, if the glassblower twisted the glass until the striations spiraled. Symmetrical or round items like candlesticks were created in two pieces and fused together and handles, the rims of pitchers, delicate necks, and other flourishes would be crafted by hand. Despite the work that went into finishing blown molded pieces, mold users had a leg up and their pieces were much more affordable than their cut glass contemporaries. The New England Glass Company and the glass companies of Sandwich, Massachusetts were top producers of blown molded glass, but few, if any, examples of molds from these areas remain in tact. Excavations at Sandwich produced only fragments, making molds from the 1820-1840s interesting, but not viable collecting items.

Pressed (or Patterned) Glass

Mold blown glass was superseded by the invention of its counterpart, pressed glass, a method that revolutionized the market and made beautiful tableware available to the populace. In 1825, American inventor John P. Bakewell patented a method of using a plunger to press molten glass into a mold. This method was faster than blowing and allowed the glass to be cast and shaped quickly before it solidified, creating elaborate designs much more easily and efficiently. Bakewell’s method was first used for furniture knobs, but spread to all forms of glassware until, by the mid-late 19th century, most glassware for the masses was pressed.

Molds in this era worked similarly to earlier creations with hinges, but became more elaborate and were designed to shape an entire piece, not only to impress it with a pattern. They were therefore more customizable and sometimes steered away from the old three-piece models. A small object like a drawer knob might require a two-piece mold, whereas a compote called for three pieces and a punch bowl for four.

Around the 1920’s, crystal from Europe was more stylish than the pressed glass that had flooded the market, but the Great Depression put a damper on crystal consumption and people returned to cheap pressed glass. The glass from this period is therefore called “Depression Glass,” and though molds and methods were similar to older items, Depression Glass came in vibrant colors and whimsical patterns to lighten the mood. Pressed glass was so affordable at this time that companies like Quaker Oats put them in boxes with food as purchasing incentives.

Molds for All

With the popularity of pressed glass ranging from elaborate to plain, everyday use items, molds existed for anything and everything. You could find molds and patterns for full table settings, holiday ornaments or collectibles animal figures. Pressed glass is still used today to mass produce glass, and though the tools have gotten more advanced, the concept remains the same. Molds exist with just as much variety as the pieces they helped shape and could offer glass enthusiasts or glassworkers a new collecting challenge.

Though not as immediately beautiful as the pieces that they shaped, molds are a critical part of our decorative arts history and could be rewarding to dig for – imagine uncovering an unremarkable metal object, only to open it up and see a popular glassware pattern! If you are interested in the history of how things are made, consider investing in the antique technology that shaped them. Glass molds appear irregularly at auction and tend to run under $1,000.

Photos courtesy:; The Allaire Collection; Bell Mead Hot Glass

Collecting the Tools of the Trade: Glass Molds