Description

Very large slab of slightly hematoid quartz whose crystals are often covered with small golden rosettes of pyrite (or marcasite? ).
This specimen comes from the Bierghes quarry in the province of Brabant Wallon, 20 km east of Lessines and 30 km west of Brussels.
Within the quarried rock, a diorite-type plutonic magmatic rock, several fissures display superb quartz in a variety of facies. In contrast to alpine quartz (15 Ma), these crystals are over 300 million years old. The magazine “Le Règne Minéral” devoted an entire article to the discoveries of this famous deposit.

A video of these quartz crystals from Bierghes :

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