Description

It’s a blende (the old French name for sphalerite) from the Pont-Péan mine, which was the most important lead and silver mine in the late 19th century.
Pont-Péan is located not far from Bruz, south of Rennes (Ille-et-Vilaine, Brittany).
For the record, it was the company of the famous Eiffel Tower engineer who built the metal headframe for one of the shafts in 1904.

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