Blue John

Yesterday we headed north of Castleton across the Hope Valley, and up onto the ridge east of Mam Tor - Millstone Grit territory.

This morning we headed up the road from the hotel, to Treak Mill Cavern. This southern side of the Hope Valley is Carboniferous Limestone upland. Caves, minerals and mining. We had a tour around the Treak Mill cavern, the only place where Blue John is still mined and worked (all the jewellery in Castleton sources the mineral from here). Fascinating, lots of exposed Blue John in the old series caves (discovered by John Miller in the 18th century when he was exploring for lead), and lots of stalagmites and stalagtites in the new series caves discovered in the 1920's. This blip is in the latter.

Bizarrely, candles and a kind of "altar" in one of the caves - a wedding took place there yesterday.

The weekend was hugely better than I was expecting. Lots of food for thought.