What are the numbers on a ball jar?
Some Ball Perfect Mason jars are found with the number “13” on the bottom. As mentioned earlier in this article, most Ball-produced jars are typically found with a mold number ranged between 0 and 15, so naturally some percentage of them will carry the number “13”.
Do you have to boil mason jars to seal them?
There is no need to boil the lids, says the University of Wisconsin-Madison Extension. They report that manufacturers changed the lid design to increase rust resistance and seal-ability and most lids no longer need to be preheated. Beyond that, boiling lids may actually contribute to their failure to seal a jar.
What does the number on the bottom of a mason jar mean?
Many Ball mason jars have a number printed on the bottom of the jar, but this is a mold number that does not indicate the year of production. Rather, the mold number tells you where the jar was positioned on the glass-making machine that was used to produce it.
Can you tell the year of a ball Mason Jar?
In fact, Ball used this patent date on their jars well into the 1930s, so this year cannot be used to accurately date a Ball jar. Ignore the mold number on the jar. Many Ball mason jars have a number printed on the bottom of the jar, but this is a mold number that does not indicate the year of production.
What do the numbers mean on a Ball jar?
The numbers can refer to the plant location, the job or batch number and the date of manufacture. The earliest Ball jars, which were hand blown, are easy to identify because the bottom of the jar will have a mark called a pontil scar.
When did Ball Mason jars start using the 3 L logo?
The 3-L logo, for instance, was only used between 1900 and 1910. This logo is called the 3-L logo because the decorative loop at the end of the logo looks like a third L in the Ball name.