Many people collect glass jars and vases. Among these collections, you are likely to stumble upon one or two antique canning jars. These jars were used for home canning and were extremely popular from the 1860s to the 1900s. Food was stored in the jar and it was sealed in one of several methods. The method used for sealing actually plays a role in the jar's value.
Old glass jars come in a variety of colors. The most common ones are clear glass, but shades of light blue, especially “Ball Blue” are also easily found. The glass was colored so as to retain the food's nutritional value because it blocked light from reaching the contents of the jar. Rare colors include amber, dark greens, black, and cobalt blues.
The earliest jars manufactured were known as “wax sealers” because of the use of sealing wax that held the tin lid to the jar. Hot wax was poured through a channel around the lip of the jar, sealing in the food. This method was used till the 1900s despite its difficulties. It was unlike the simpler Lightning method, which consisted of using metal wires as leverages to hold down the glass lid. The first jar to use the method was embossed with the word “Lightning”, hence the name of the method.
The first jars to use a screw-on zinc cap seal were Mason glass jars. Among the most popular canning jars, Mason jars were made of soda-lime glass. They were invented by John Landis Mason in 1858, and are actually among the first of the glass canning jars. The jars come in a variety of sizes, shapes, and colors. It's sealing method consisted of an inner flat piece of metal covered by screw-on ring, which during the canning process created a partial vacuum and sealing the lid. The method was patented on November 30, 1858, which explains why Mason jars were embossed with “Patent Nov 30th 1858” all the way into the 1900s. Jars with these patent are among the most popular Mason jars.
Antique canning jars, such as Mason jars are valued based on its age, condition, and on rarity of the color, size, or shape of the jar. These characteristics can be determined through the jar's mold and production marks as well as its method of closure because different sealing methods help identify the jar's age. Today, many of the absurd closure methods fetch the highest prices among collectors because only a few jars were made using the failed methods. Among them, you are likely to find the priciest Mason jar, which was sold for $30,000.
Antique Jar Trivia: Apart from the role they played in food's history, antique canning jars also played a role in war history. Mason jars, which were made of thick glass that was resistant to premature shattering when thrown at high altitudes, were used during the Vietnam war. The jars were used to hold back the safety levers of grenades, allowing troops to deploy grenades from helicopters with the assurance that they wouldn't detonate till the glass itself shattered.