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Show 40 • VlSion for the forthcoming milllions that ~hortly shall people your ample valleys, and golden hills--and above all, recollect that" righteousness exalteth a nation." / , • APPENDIX. TESTS BY WHICH GOLD MAY BE DETECTED. ExTERNAL CHARACTERISTics.-Gold is found native, and alloyed with copper, iron and silver. Native gold is of a bright yellow colour, with a density of 19'3, is pre-eminently ductile and maleable. These qualities distinguish it from most of the other metals. Its primary form is the cube, but it occurs under several modifications, particularly the octohedron; it is also found in threads or stems, variously twisted, and in spangles, or rounded grains, which is proved to be its original form, instead of the effects of at1rition. It is often combined . with iron pyrites and '\Vith specular oxide of iron ; also with tellurium and PalJadi~m. 'fhe electrum or argen .. tiferous, is di5tinguished by its white colour, with an amber tinge, and contains in one hundred parts, 64 of gold and 36 of silver. When gold is found associated with cop per, or iron pyrites, the metal may not always be readily recognised, when fresh fractured; but on exposure to the ai::-, the base metals become oxy dized, whilst the gold remains unaffected, and becomQs conspicuous, even when it constitutes only one-five millioneth part. ITs GEOLOGICAL PosiT ION.-Gold is found in granite, as at Salsberg and La Gardette, in France, associated with beds of quartz and specular iron; in mica slate, as in Villa Rica, in Brazil and Virginia; in syenites and |