Commander Nick Bartlett was a retired Submariner in the Royal Navy.
He lived in Baslow in Derbyshire close to the gates of Chatsworth House where he had spent many years as a volunteer guide.
His interest in minerals stemmed from a general interest in engineering and natural history.
He sold his collection in 2004 after deciding it was time to retire.
The collection comprises some 1500 specimens from the British Isles, many obtained from his good friend George Fletcher.
One particular piece of note from the collection was a huge (24cm) and very early Oakstone lump, used as a door wedge!
