ORE MINERALOGY OF THE CLARGILLHEAD VEIN, TYNEHEAD, CUMBRIA: THE FIRST REPORT OF NATIVE SILVER FROM THE NORTHERN PENNINE OREFIELD

摘要

Veinstone samples collected from old workings at Clargillhead, Tynehead, Cumbria, contain assemblages of sulphide, sulphosalt and sulpharsenide minerals which add to the diversity of ore minerals found within the deeper levels of the zoned Northern Pennine Orefleld. The veins from which these samples were collected coincide with the area from which lead ores with the orefteld's highest concentrations of silver have been recorded, above the Tynehead Cupola of the Caledonian Northern Pennine granitic batholith. Very small grains of native silver, of supergene origin, within these samples represent the first record of this mineral from the Northern Pennine Orefleld.