. The prospector's field-book and guide in the search for and the easy determination of ores and other useful minerals. ing nitric acid. Itwill not dissolve in nitric or hydrochloric acidseparately, but it does dissolve in the two whencombined, and then the acid is known as nitro-muriatic acid or aqua regia. Proportions: onenitric to four muriatic. But it is not always a trustworthy sign that par-ticles are gold because they will not dissolve innitric acid. Some seemingly gold-colored particles will not dissolve in nitric acid, and yet contain nota trace of gold. The simplest instrument for th
. The prospector's field-book and guide in the search for and the easy determination of ores and other useful minerals. ing nitric acid. Itwill not dissolve in nitric or hydrochloric acidseparately, but it does dissolve in the two whencombined, and then the acid is known as nitro-muriatic acid or aqua regia. Proportions: onenitric to four muriatic. But it is not always a trustworthy sign that par-ticles are gold because they will not dissolve innitric acid. Some seemingly gold-colored particles will not dissolve in nitric acid, and yet contain nota trace of gold. The simplest instrument for the discovery of goldand the estimation of the value of an auriferousmaterial in which the gold is contained in a freestate, is the ordinary miners pan, a circular dish ofRussian sheet-iron, about 12 inches wide and 3inches deep, with sloping sides. There should be aslight indentation all round where the sides jointhe bottom, so as to afford lodging for the goldgrains, and the more rusty it is the better. A fry-ing pan free from grease will answer very well on apinch. The South American batea, Fig. 40, made Fig. of hard wood in a solid piece, and hollowed out likea shallow funnel, is a superior implement when incapable hands. Another good substitute for thispan is a kind of magnified shovel without handlemade of linden wood and provided with a verticalwall on three sides. The wooden implementsshould be slightly charred on the surface to showup the gold grains, and should not have been usedto hold mercury or amalgam. The object of panning out, as the operation withthe pan or batea is called, is to settle and collect atthe bottom of the pan the heaviest portions of the GOLD. 109 material subjected to the test. Simple as the pro-cess of panning appears to be, dexterity is only ac-quired by considerable practice. In outline theoperation is as follows : A quantity of the dirt to be washed is placed inthe pan, sufficient to occupy about two-thirds of itscapacity. The pan with its
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectprospec, bookyear1903
