Here is the hard to find Jade-ite Fire King Restaurant Ware 6-ounce coffee cup number G215. This small mug was listed as Item G215 Restaurant Ware in early Fire King Jade-ite advertisements, and is made of heavy, plain, opaque glass.
The 6-oz cup measures 2-3/4 inches tall and 3-1/8 inches in diameter with another 7/8-inch for the handle.
The embossed mark reads "Fire King" between the words "Oven Ware" followed by "3 Made in USA" with 5 embossed dots above the word "Oven." This popular Restaurant Ware was made by Anchor Hocking from 1948 to 1967.
There are two tiny smooth nicks on the inner rim and the outside bottom of the cup has some stains. There is no other damage.