Baryte, Barium sulphide, BaSO4. Bryntail mine, Nr Llanidloes, Central Wales Orefield. A few specimens recovered from the sorting platform at the remains of the mine. Notice the layered structure, which is not uncommon in specimens from this mine.
Galena, PbS. Pen Dylife mine, Nr Staylittle, west Wales. Thin deposits of galena occupying faults in fractured host rock. There are no complete crystals in the specimens, but the typical galena cleavage is observed in the exposed fracture surfaces. These specimens were recovered from the wall of a long abandoned open cut excavation.
Quartz, SiO2. Bryn y Rafr mine, west Wales. Very small druzy crystals of quartz in host rock which has been coloured red by iron. The crystals are well formed, and are deep red in colour. The specimens have no trace of other minerals.
Calcite, Calcium carbonate, CaCO3. Nantiago mine, Central Wales Orefield. The uncommonly flat bladed crystals of calcite are deposited on a piece of host rock of indeterminate nature. This type of crystal is more usually associated with baryte, which I don't think has been recorded at this mine. The gangue mineral at Nantiago is calcite, and the spoil heaps are littered with the mineral, mostly displaying it's rhombohedral habit.
Calcite, Calcium carbonate, CaCO3. Nantiago mine, Central Wales Orefield. The bulk of this specimen is massive calcite. One face is covered with bladed crystals. This type of calcite crystal is not very common, and in appearance, the specimen could easily be mistaken for baryte.