An Atlas E-Z Seal jar in an unusual cornflower blue color sold for over $100.

How much are old jars worth?

Typically, the smaller or more common antique jars can go for about $20 apiece, but the more rare versions can sell for as much as $300.

Are Atlas Mason jars good for canning?

The jars being stamped Mason Atlas has more to do with marketing than anything else. They are lighter than actual mason canning jars, although the seals and rings for mason jars will fit on them. Therefore, you should NOT use empty Classic jars for home canning!