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PROPERTIES OF GOLD.

also been discovered at the same place, in sand, covered withturf, and adjacent to a rivulet.

Gold is also met with in a particular sort of argentiferous cop-per pyrites, called in Hungary Gelf. This ore is found eithermassive, or crystallized in rhomboids, or other irregular qua-drangular or polygonal masses. It exists likewise in the sulphu-rated ores of Nagaya in Transylvania. These all contain themetal called tellurium. Berthollet and other French chemistshave obtained gold out of the ashes of vegetables.

PROPERTIES OF GOLD.

Gold is of a brilliant rich yellow colour; no other substancein nature is so heavy, platina excepted. Its specific gravity is19.3. Its hardness is not very considerable. Its ductility is soconsiderable that a wire of an inch in diameter supports aweight of 50Olb. without breaking. It melts at 32° of Wedg-wood’s pyrometer, and when suffered to cool slowly crystallizesin short quadrangular pyramids. By an intense heat, as that of amirror, it is volatilized. It is incapable of oxidating at any tem-perature which our furnaces can yield. It is a good conductorof caloric, electricity, and galvanism. The two last agents in-flame it, and convert it into a purple oxid which is volatilized inthe form of smoke. It does not unite with hidrogen, carbon orwith sulphur ; though the latter when in the state of a sulphuretdissolves it. Phosphorus combines w'ith it; arsenic, bismuth,and antimony form an intimate union with it. It easily alloyswith mercury. With silver it forms an alloy of considerable duc-tility. Copper heightens its colour and renders it harder withoutmuch imparing its ductility. Tin and lead greatly impair its te-nacity. With platina it forms an alloy which is considerablyductile. Combined with zinc it affords a very brittle and hardmixture susceptible of a beautiful polish. It unites well withiron and hardens it remarkably. Its ductility and malleabilityare far greater than any of the rest of the metals.