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<br />Pseudomorphs of Gold. <br />Pseudomorphs of gold are naturally formed from the tellurides of gold, calaverite, <br />sylvanite and krennerite. Pseudomorphs from these minerals are common in the <br />supergene regions of a very rich hydrothermal telluride vein. The rarity of these <br />pseudomorphs is explained by several different factors, which are based on historical <br />facts in the course of their discovery <br />(1) The discoverer was not interested in the preservation of these minerals, they were <br />discovered by the "butcher, the baker and the candle stick maker" of that bygone era. <br />The early prospector was only interested in putting "beans and bacon" on a starving <br />prospectors table. The pseudomorphs were the first gold to be mined in a prospect and <br />went straight to a mill, or were ground up in an "arastra'and panned out by the miners <br />themselves. <br />(2) Below the oxidized level of the prospect (3 to 10 ft.) the vein only contained "fresh" <br />telluride minerals, which were also ground up for the gold they contained. Again, no <br />thought was given to the value of specimen material as a future, marketable item. <br />(3) Pseudomorphs of gold are difficult to recognize, but because they are formed by <br />several different natural ways, and from several different minerals, they differ in their <br />appearance. The ugly rusty color of these crystals (from sylvanite) makes them appear as <br />rusty blobs on an iron stained rock, hardly an attractive attribute. The "float" has long <br />since lost the friable remnants of gold on the outside of the float rock, (rusty gold or <br />flour gold) and the float rock must be broken to see them inside the rock. There are <br />however; telltale cavities left by the original telluride crystals that are difficult to <br />recognize unless you are looking specifically for them. The above mentioned <br />pseudomorphs are those that result from ground water leaching of tellurium from <br />sylvanite. The pseudomorphs of gold that are formed by the loss of tellurium by heat <br />from sylvanite are of a light yellow metallic color because of the silver in the original <br />sylvanite crystal. This results in pseudomorphs of electrum, which are often called "free" <br />gold. Pseudomorphs that result from calaverite by the loss of tellurium from exposure to <br />plutonic or volcanic heat are of a darker metallic yellow color and are free gold in the <br />true sense of the word, however; they still retain the monoclinic crystal habit indicative <br />of the original calaverite crystal and are pseudomorphs unless the heat is intense enough <br />to melt the gold insitu. <br />(4) Even to this day, the pseudomorphs of gold after calaverite, sylvanite and krennerite, <br />which are altered by the loss of tellurium by heat, are not recognized nor accepted for <br />what they really are and are called just "gold." This may seem like an insignificant point <br />but it is a very important consideration in explaining the origin of free milling gold. <br />When a mass of molten magma rises up into the upper mantel or higher, into the crust, <br />from a disturbance of the metallic core, it forms a magmatic body known as a pluton. The <br />pluton must contain the essential ions of gold, silver and tellurium in order to supply