Comment Comment by kreldjarn There are also radioactive tiles decorating the Caltech campus: https://www.flickr.com/photos/lapie/3340318920/Apparently there was a brief period in the 20th century when this was a popular way of making yellow glazing. parent kreldjarn 3 years ago
Apparently there was a brief period in the 20th century when this was a popular way of making yellow glazing.