Original question: Here is the backside of a commemorative porcelain plate for the Mohawk & Hudson Railroad. I haven't owned one of these, but as far as I know, the printing appears to be on top of the glaze (i.e., the opposite of an underglaze ink stamp). Is there a proper term (or nickname) for this type of marking?

UPDATE: This marking is called a maker's mark. The style is known as both overglaze and on-glaze.

Thanks to Jack Snyder and The Spruce Crafts website for the information.

Photo credit: eBay