Please use caution when using older jars. My family was canning apple butter that we had cooked over a open fire in a cauldrin looking pot, and when we was adding this to the jars, my job was to tighten the lids and wipe the jar off. Well, needless to say the bottom of the jar blew off from the heat, and the hot liquid melted the skin on my wrist. It is healed now, but left a bad scar. Just use caution.