Radium Brand Enamel (ca. 1905 to 1930)
This product was manufactured by J. L. Prescott Co. of New York which operated from 1870 to 1945.
The enamel would be used to paint the outside of oil or gas stoves as well as the stove pipes.
Some of the advertisements for "Radium Enamel" that I have found are clearly referring to this product. These ads date from 1905 to 1930. I have also seen this specific product in a 1928 listing of hazardous materials. In other cases, the radium enamel being advertised was a glow-in-the-dark paint or an enamel of the type used inside food storage appliances.
Size: 3 3/4" high, 2 1/2" diameter
Price: 12 to 25 cents
Gorham, D. Milne, W.D. Industrial Fire Hazards and an Encyclopedia of Hazardous Materials. 1928.