Sphalerite, Zinc sulphide, (Zn,Fe)S. Dylife mine, Central Wales Orefield. Brecciated rock from ore deposits, consisting of light grey country rock, possibly limestone with sphalerite in massive form. Also very fine druzy quartz and very minor galena. The sphalerite is overlying the quartz in several places, indicating that the sphalerite was a later deposit.
Nantiago mine, Central Wales Orefield. This is a detail from sphalerite, galena, and calcite 1. The galena cubo-octahedral crystals are in the lower half of the photograph, and the sphalerite aggregate is in the upper half.
Nantiago mine, Central Wales Orefield. Sphalerite and galena filling crevices in fractured calcite. The sphalerite is a coarse aggregate with a very deep red colouration, and the galena is mostly in the form of cubo-octahedral crystals. The ratio is approximately 90:10% in favour of the sphalerite.
Chrysocolla is a hydrated copper phylosilicate mineral found in the weathering zone of copper deposits. Geufron mine, Central Wales Orefield. Detail enlargement from chrysocolla 1. The globular nature of some of the encrustation is more apparent. The adjacent mine of Hafod Feddgar has an adit with a very large area of encrustation on both walls and floor which is very similar in appearance.
Chrysocolla, ia a hydrated copper phylosilicate mineral found in the weathering zones of copper deposits.Geufron mine, Central Wales Orefield. Specimens were collected from the spoil heaps at the mine. Specimens are abundant and are from the surface or just below. The encrustations are mostly without detail, but sometimes include small areas of globular growth. The encrustations are believed to be Chrysocolla, but will need X-ray diffraction to verify.