I'm trying to help my mother sale off some old fruit jars. For the most part, all she has are the more typical blue Ball perfect Masons and some Atlas strong shoulder in various sizes, but one is a quart size, Keystone Mason Patent Nov 30th 1858. It is a round shoulder, Aqua colored jar with air bubbles and the number 15 on the bottom. It has several lip chips, but overall is in pretty nice condition. Can anyone help me out as to what one like this might be worth?