Opening an old cupboard can sometimes feel like discovering a collection from another era, and these tiny metal objects are a perfect example. Their rounded shape, open bottom, and hundreds of small indentations can make them difficult to identify if you grew up after hand sewing became far less common.

They are sewing thimbles, small protective caps traditionally worn on a finger while sewing by hand. Their main purpose was to protect the fingertip while allowing someone to push a sharp needle through fabric without repeatedly hurting themselves.

Those hundreds of little dimples aren’t simply decoration. The blunt end of the sewing needle rests against one of the indentations, which helps prevent it from slipping sideways while pressure is applied. This becomes particularly useful when pushing a needle through thick fabric or several layers of material.

Thimbles have existed for centuries and have been produced from materials including brass, silver, bone, wood and other metals. Older households often kept several because sewing, repairing torn clothing, replacing buttons and altering garments by hand were ordinary domestic tasks rather than occasional hobbies.

So the mystery has a wonderfully simple answer: these are old-fashioned sewing thimbles. Grandma would have slipped one over the finger she used to push the needle, turning those strange little metal caps into practical protection during hours of sewing and mending.