Glossary of Fruit Jar Terms

As used on this website

Ball Logo – the representation of the word ‘Ball’ embossed on a fruit jar. Variations: Standard, Hybrid, Modified.

Band – threaded ring, usually metal, used to hold a lid on a jar

Bead – ring of glass on a jar, usually used to hold a wire in place or to serve as a sealing surface.

Bead Seal – type of mason finish with a rubber sealing ring that rests on a bead of glass just below the threads. Compare to ‘shoulder seal.’

Cap – solid closure, usually metal, often threaded, that seals a canning jar in conjunction with a sealing rubber.

Closure – the mechanism for sealing a jar

Double Helix

Finish – the part of a canning jar that contains the closure, usually the upper part of the jar. From the fact that applying the neck area was how a hand-blown jar was ‘finished’.

Full-wire – type of lightning finish jar that has a tie wire around the neck, below a bead of glass, holding a metal eye for the wire bail to fit into.

Gasket - flexible material, often rubber, used to seal the home canning jar

Improved Mason – sealing mechanism consisting of a straddle-top glass lid held in place by a zinc band. The seal occurs above the threads.

Lid – flat part of the closure held in place by a band, clamp, yoke, etc.

Lightning finish – sealing mechanism consisting of a glass lid held down by a wire bail that snaps into place. Called “lightning” by the inventor to emphasis that it could be opened faster than the standard mason jar.

Mason finish – sealing mechanism consisting of a jar with glass threads. Invented by John L. Mason, the first versions sealed on the shoulder of the jar with a rubber ring and zinc cap.

Rubber Ring – sealing mechanism, usually used with a cap or glass lid, for a canning jar. Traditionally red in color.

Shoulder Seal – type of mason finish with a rubber sealing ring that rests on the shoulder of the jar. Shoulder seals usually indicate an older jar, as they were replaced by bead seal jars.

Wax Sealer – canning jar that seals using melted wax in a grove around the top of the lip with a tin-plated lid and thin wire clamp.