Found this while metal detecting this morning. Several old rusty screw-on lids, tin and then the jar was heard while digging. I’m guessing possibly mustard(?). I haven’t looked up the year or plant yet. This was very close to the base of an old capped cement well/cistern. It is also very close to where my underground power feed is located. I won’t dig it until I’m sure it is safe. I love finding old dumps. 👍🏼