" Encased in a glass disc, inscribed with the words "the mould that first made Penicillin," and signed by Fleming himself, the little sample comes from the collection of Fleming's niece,..."
http://www.npr.org/sections/thetwo-way/2017/03/01/517979196/this-tiny-patch-of-mold-cost-one-lucky-buyer-nearly-15-000?utm_medium=RSS&utm_campaign=world