Copper massive sulphide

Copper deposits, 440,450 Massive sulphide Crandon, USA, 285, 286 Metasomatic... 

Silver has many intensive lines in breakdown spectrum, the strongest ones at 328 and 338 nm in the UV part of the spectrum and at 520 and 546 nm in the visible (Fig. 8.42a, b), which it may be potentially used in radiometric sorting. Silver is relatively uniformly distributed in massive sulphide ores (average values for the deposits 10-50 ppm), but local enrichments occur (up to 150-300 ppm of Ag). Silver usually has higher concentration comparing to gold and in certain cases may be analyzed by online LIBS. For example, we have positive laboratory scale experience with 10 samples of copper bearing rocks from Peru. It is very rare... 

That the atomic weight of uranium lead is extremely variable has already been shown. In order to interpret this variability its sources must be studied both geologically and mineralogically. On the geologic side of the question the uranium ore can be divided in to three principal classes, which are sharply distinct. The definitely crystallized varieties of uraninite occur in coarse pegmatites, associated with feldspar, quartz, mica, beryl, and other minor accessories. The massive pitchblende is found in metalliferous veins, together with sulphide ores of copper, lead, iron, zinc, and so forth. As for camotite, that is a secondary mineral, found commonly as an incrustation on sandstone, and often, also upon fossil wood. There may be other modes of occurrence, but these are the most distinctive. 

Combined with arsenic, nickel occurs in the mineral niccolite, nickeline, ox copper nickel, NiAs. It is rarely crystalline, but when it is the form is hexagonal hardness 5-5 density 7-5. Its coppery rcdl hue is characteristic, only two other minerals, namely, copper arsenide and breihauptite or nickel antimonide, NiSb, bearing any resemblance to it. This latter mineral occurs at Andreasberg, in the Harz, is usually massive, and often associated with a considerable amount of lead sulphide. Crystals are rare hexagonal. 

A double sulphide of copper and iron known as Chalmersite, CuFe2S3, occurs in the ore deposits of the Prince of Wales Sound, Alaska,2 and in small quantities in Brazil.3 It is massive, pale yellow in colour, and strongly magnetic, which latter property enables it to be readily separated from the copper pyrites with which it is intimately associated. Density 4 04 to 4 68. The crystals arc rhombic,... 

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