GOLD, the most valuable of all the metals, is of a bright yellow colour when pure, but becomes more or less white in proportion as it is alloyed with other metals. It is the heaviest of all the metals, platina only excepted.

Native gold is found in veins, but these are seldom or never very large. It is generally very minutely disseminated, and can only be detected by washing the pulverized mineral strata in which it exists, such as the sand of rivers, and the mould of valleys and plains, whither it had been transported by running water. Gold is obtained from the alluvial soils of several islands in the Indian Ocean; from several parts of Africa, a part of which is called the Gold Coast, on account of the quantities of this metal formerly found there; from the sands of several European rivers, and also those of the United States: but by far the greatest quantity of gold is found in the South American mines. Humboldt estimates the average product of gold per annum, of South America and New Spain, at nearly 11,000,000 dollars. In Russia and the United. States there are also mines of gold. Adding the produce of the American to that of the Russian mines, their total produce during each of the four decennial periods ending with the year 1829, has been estimated as follows by Macculloch, in his Dictionary of Commerce.
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The gold produced in the United States in 1832 was in value above L.135,000. It is chiefly obtained by washing the soil in the valleys. The produce of the European mines of Hungary, Saxony, and other places, has been somewhat vaguely estimated; but it must be trifling compared with the quantities derived from the new world. With regard to the quantity of gold annually consumed, no correct idea can be formed, because it is utterly impossible to estimate how much of old gold is wrought up in the fabrication of new materials. As to the future supply of this precious metal, it seems probable that it will increase when the anarchy in which the South American states have been so long involved shall terminate. See Mines. Gold Coast. See Guinea. Gold Wire, a cylindrical ingot of silver, superficially gilt or covered with gold at the fire, and afterwards drawn successively through a great number of little round holes, of a wire-drawing iron, each less than the other, until it attain the fineness required.

Gold Wire flattened, is the former wire flattened between two rollers of polished steel, to fit it to be spun on a stick, or to be used flat, without spinning, in certain stuffs, such as laces, embroideries, and the like.

Gold Thread, or Spun Gold, is flattened gold, wrapped or laid over a thread of silk, by twisting it with wheel and iron bobbins.

Gold Leif, or Beaten Gold, is gold beaten with a hammer into exceedingly thin leaves, so that an ounce may be extended into one thousand six hundred leaves, each three inches square, in which state it covers more than 159,052 times its former surface.

Gold Plates for Enamelling are generally made of ducat gold, the fineness of which is from 23⅜ to 23J carats; and the finest gold is the best for this purpose, unless where some parts of the gold are left bare and unpolished, as in watch-cases, snuff-boxes, and the like, for which purpose a mixture of al oy is necessary, and silver is preferred to copper, because the latter disposes the plates to become tarnished and to turn green.

Shell Gold is that used by those employed in gilding and S illuminating, and. with which gold letters are written. It is made by grinding gold leaves, or gold-beaters’ fragments, with a little honey, and afterwards separating the honey from the powdered gold by means of water. When the honey is washed away, the gold may be put on paper or kept in shells. When it is used it is commonly diluted with gum-water or soap-suds. The German gold powder, prepared in this manner from the Dutch gold leaf, is generally used; and when it is well scoured with varnish, it answers the end in japanners’ gilding as well as the genuine.

Gold Size, for burnished gilding, is prepared of one pound and a half of tobacco-pipe clay, half an ounce of red chalk, a quarter of an ounce of black lead, forty drops of sweet oil, and three drams of pure tallow. Grind the clay, chalk, and black lead, separately, very fine, in water; then mix them together, add the oil and tallow, and then grind, the mixture to a due consistence.