There are several stamps (maker's marks) on the front of this mug, but I can't make them all out. One says "American", one says "USA" . One is circular, and one is a shape. The last one is words that I can't make out. It looks like all the stamps were hit twice, which doubled the imprints and made them difficult to read.
I tried to enhance them in a photo below, but they don't look any better.
The emblem on the front says, Texas Renaissance Festival - Lift Up Your Cares.
I'm guessing this tankard was purchaed in the late 70's, making this mug at least 35 years old. I don't think it would take much to polish out the scratches. It was used for years as a pencil holder.
This beer stein is about 4.5 inches tall and about 5.5 inches across, including the handle The mouth opening is about 3 inches wide.
20.00 or Best Offer