Description
This is a very dense combination of galena and blende from the Pont-Péan mine, which was the largest lead and silver mine of the late 19th century.
Pont-Péan is located not far from Bruz, south of Rennes, in 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.
This post is also available in: French