If, like me, you thought that the English Heritage Blue Plaques on buildings that commemorate their links with a famous person were cast metal, you'd be wrong! Apparently they are ceramic, and made in Cornwall nowadays by Frank and Sue Ashworth who have been making the plaques since 1984.
They rate a mention and wee bit of a story in the article about Blue Plaques in today's news here:
http://www.bbc.co.uk/news/uk-england-36322761