Chrysolite Graniteware Large Cup or Small Pot 100 Plus Years Old

This looks like a cup but it is 6" wide and 5" deep. Possibly a cup who is cutting down to 1 cup a day. I thought this could possibly be a chamber pot but it has scorch marks on the underside thus it is for cooking. So everyone can relax when they have their one drink a day from this cup. Actually it is more likely a pot due to the size and scorch marks.
The color here is called Chrysolite which is a bluish green color. Possibly because that is the mineral used to make the color. The coating here is actually glass which makes it easy to clean but easy to damage too. When buying graniteware or enamelware I always want to see some damage spots to avoid getting a repro piece. This chips easily so there should be chips on it. Highly likely it has passed the century mark and then some. Still not sure when they stopped making the swirl pattern but I believe it is pre 1920.