Unknown Glass Jar? Very Thick Glass - Depression

This is a Large, Heavy and Thick Glass Jar... 2 pounds, 8 ounces... 5 1/4" across the top.. Top is 12-sided.. No Lip inside and smooth lip on outside.. 5 3/8" Tall... Bottom is 4 3/8" across... 1/4" thick walls... Found in an old home and no one can figure out what it is used for... Hope you can help... Thank you for your assistance...