Next time you're strolling through the glassware aisle at your local Goodwill, you may want to pay close attention to the Mason jar section. Mason jars aren't just a continually trending home decor ...

You may have some old, original Mason jars lying around Grandma's attic, and if you spot a jar with this number on it, you're about to become a bit richer.

Add Yahoo as a preferred source to see more of our stories on Google. close up of light blue vintage mason jars at flea market - Kimbra Ritchie/Getty Images The first step is to look for signs of age, ...