Hematite

Hematite

Hematite Nodule,  Fe2O3  Iron oxide. with Siderite and Quartz.  This specimen was found on my final visit to Marine colliery waste heaps. Hoping to find some Millerite, I arrived to find that the waste heaps had been landscaped out of existence. As I was despondently leaving the remaining tiny car park, I spotted this nodule by the entrance, which did at least give me something to show for my 136 mile round trip. The centre of the nodule is lined with tiny platey Siderite crystals, with two small crystals of Quartz.

Jasper

Jasper

Jasper,  Mookaite var.  SiO2 , is not a mineral as such, but is a rock. It is formed as a sedimentary rock from the weathered products of a cretacious siltstone in the Carnarvon basin in Western Australia. In particular it derives it's name from Mooka station, where it was first found. Jasper is an aggregate of microgranular quartz, and chalcedony. The specimens reddish colour is the result of iron impurities, and the typical conchoidal fracture of quartz is apparent. This specimen was collected by Jim Nicholls, co-founder of the club, while he was working in the area.

Hematite

Hematite

Hematite,  Fe2O3  Iron oxide, with Siderite,   FeCO3 Iron carbonate. The Hematite in this specimen is in the form of many angular shards, which were created as the result of hydraulic brecciation. The spaces and voids have been populated by small platey crystals of Siderite. Also on the specimen is one " herkimer " quartz crystal. The specimen was collected from Marine colliery waste tips, near Ebbw Vale, south Wales

Barite

Barite

Barite, or Baryte,  BaSO4   is Barium sulphide. This specimen is peculiar to cliffs on the north coast of the Isle of Sheppey, in Kent. The cliffs, which are in the London clay, are host to large septarian nodules. The nodules have cracks which are lined with pale mustard coloured Calcite, on which there are radiating greyish white Barite crystals. How this type of  mineralisation  occurs seems to be a mystery.    

Chalcopyrite

Chalcopyrite

Chalcopyrite,  CuFeS2  is a Copper Iron sulphide mineral. It is the most important ore of copper, and the two most important sources are found in  volcanogenic massive sulphide deposits, and sedimentary exhalative deposits ( Hydrothermal deposits ). Small crystals such as these shown on the specimen are quite commonly found in nearly all mining exploration sites in the U.K. This specimen is reputed to be from Kellingly mine, near Knottingley, Yorkshire. The field of view of the insert is 7mm. and there are even smaller crystals peppered on the surface, which is completely covered with minute clear, pale yellow/brown fluorite crystals.