Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/354

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In Schist—both micaceous, and of other descriptions from S. Agness—in small veins passing in various directions through light coloured schist from St. Agness—crystallized, on rounded masses of aggregated fragments of schist (grauwacke) from Relistian mine.
In Chlorite—from Polgooth mine—in compact chlorite with imbedded crystals of mispickel from Relistian mine—on crystallized chlorite from Huel Unity.
In Schorl—from Huel Unity, and some mines in St. Just.
In Carbonate of Lime—very compact and semi-transparent, from Polgooth—with rhomboidal crystals of carbonate of lime from the same place—and with schiefer spar, also from Polgooth.
In Topaz—with quartz and topazes of a light yellow; on topaz in mass, as I suspect, in which are imbedded crystals of tin and quartz—with topazes of a greenish cast, imbedded in mica on decomposing granite—with topazes and chlorite, on granite with white topazes, crystallized phosphate of lime, and silvery mica on granite, from St. Michael's Mount. Fom what districts the other specimens were brought is unknown, but they are from Cornwall.
In Calcedony—covered by white decomposing chalcedony and by blue chalcedony; both from Pendnandrae mine.
In Fluat of Lime—disseminated through brownish fluor, intimately mixed with chlorite from Pendnandrae—disseminated through a mass of white fluor, transparent and opake, and very fusible, from Huel Unity—with fluor, purple on the surface, quartz and chlorite on schist, from St. Agnes—imbedded in[1] Chlorophane,
  1. The mine called Pednsndrae is, I believe, the only one in this country, in which chlorophane has been found. I obtained this specimen from it in 1805, which together with another, also in my possession, in which the chlorophane is almost completely imbedded in semitransparent calcedony, is the only specimen that has been noticed. It is traversed in various directions by minute veins of chlorite, occasionally embedding yellow copper ore and oxyd of tin. It is hard; scratches glass easily; its fracture is shattery and splintery. Its general colour is purplish; it is transparent at the edges, and the fragments are very transparent; a thin piece held for a short time in the flame of a candle, emits a brilliant green light, which becomes very brilliant by placing it on a live coal, from which, if it be taken at about the height of its light, it may be repeated, though with diminished effect; by frequent repetition it becomes nearly colourless. It does not fly even in the centre of a common fire.