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Also in the sale, the Nobel prize bronze medal.
Two samples of mould that Sir Alexander Fleming used to produce penicillin have emerged for sale as part of a remarkable £15,000 archive relating to the legendary scientist.
Both specimens of the yellow-green Penicillium Notatum fungus are contained on a glass disc and date back to the 1930s when Fleming was developing his 1928 discovery of penicillin.
The treatment has gone on the save millions of lives across the world.
Indeed, as part of the archive that has emerged at Bonhams is a poignant letter of thanks from a father to the biologist for helping to save his daughter's life.