For six millennia, we have been drawn to gold. As our civilizations – defined in terms of settled communities, complex social structures, agriculture, written language and technology – have risen and vanished, we have used gold as a medium for artistic expression, a symbol of stature and wealth, a spur for commerce, a plea for spiritual favor, a celebration of kings and gods, and a clarion call to conquest.
For instance, as Spain launched her exploration and colonization of the Americas, King Ferdinand, according to the National Mining Association’s The History of Gold, exorted his conquistadors to “Get gold, humanely if you can, but all hazards, get gold.” Columbus, describing the results of his first voyage in a letter to Ferdinand, spoke of rivers that “contain gold,” great “mines of gold,” and “incalculable gold.” Hernan Cortes, explaining why he set out to conquer Mexico’s golden Aztec empire in 1519, said that “I came here to get rich, not to till the soil like a peasant.” In 1540, Don Francisco Vázquez de Coronado led his epic expedition across our Southwest desert land in a chimerical search for the Seven Cities of Gold. By 1660, said J. H. Elliott in his Imperial Spain, 1469 – 1716, the progeny of Columbus and Cortez had delivered more than 200 tons of the gold of the Americas to the famous Gold Tower on the Guadalquivir River in Sevilla. That gold helped rejuvenate the moribund economy of Europe.
When John Marshall discovered gold while building John Sutter’s sawmill near Sacramento in 1848, he triggered the California gold rush, a human tide of migration across the deserts and prairies of the West. In following years, prospectors invaded the mountain ranges that crossed the Chihuahuan, Sonoran and Mojave Deserts, heedless of Apaches and terrible hardships in an obsessive search for gold. They left abandoned mines, tailings, rusting shovels and pans, gloomy cemetaries, ghost towns and legends as their legacy.
What is Gold, Anyway?
Pure gold – like, for example, pure mercury, lead, silver, copper, iron or aluminum – is classified as a metallic element. (By definition, an element comprises only a single type of atom.) For comparable volumes, gold weighs some 19.3 times more than water, 1.4 times more than mercury, 1.7 times more than lead, 1.8 times more than silver, 2.2 times more than copper, 2.4 times more than iron and 7.1 times more than aluminum.
If comparatively rare, gold nevertheless occurs on every continent on earth and in the waters of the sea. It is, according to the Prospectors Paradise Internet site, “mined in deserts, high mountain ranges, in the deeply weathered soil of the tropics and in the permanently frozen ground of the Arctic.
“In America nature was extremely generous. Thirty-two states have recorded significant commercial gold production. The highest yield areas are located within the western states. The recreational gold prospector can find gold in practically every state of the union.”
Also treasured by scientists and technologists, gold has been used to treat some forms of arthritis and related conditions. It has been used to tag proteins in studies of human disease. It has been used to tint the visors of astronauts’ helmets, coat the impellers in the space shuttles’ liquid hydrogen pumps, and to coat the mirror of the Mars Global Surveyor telescope.
It is no wonder, as Prospectors Paradise says, that our ancestors “believed gold contained a hidden, internal fire, a gift from the Gods with mysterious healing and magical powers.”
 | Video- Riding Your SUV or ATV Over Gold One of the most famous prospectors of the time, trapper/gold seeker “Pegleg Smith” traveled through the Anza Borrego region. It's rumored he discovered black gold somewhere in the east part of the Borrego desert. |
How Did Gold Get Here?
Gold, the alchemists believed, could be made in their dark and primitive laboratories, provided they could just find the magic tincture they called “Philosopher’s Stone.” They believed that this mysterious substance could not only heal the soul, cure the sick and extend life, it could transform the lesser metals into gold. It would open the way to universal happiness. (If the alchemists failed in their search for Philosopher’s stone, they did lay the foundation for modern chemistry.)
Gold, a part of the primal stew of elements that gave birth to our planet, settled well below the surface. With the passage of time, some gold came into contact with ground water that had been heated by molten rock. If pressures were high and the geochemistry was right, the gold as well as other minerals like quartz, galena and pyrites dissolved into the water. Superheated, the water, laden with its burden of gold and other materials, surged upward, driven by pressure toward the surface. It intruded into fractures and folds of fault zones, contacts between differing rock types, openings of porous rock formations, and other cavities near the surface. As heat and pressure diminished, the water yielded back to the earth its load of gold and the companion materials, which precipitated out of solution to form veins, or lodes.
Chris Ralph, in an Internet paper called “The Geology of Coarse Gold Formation,” said that “The most common conduits for these solutions are natural fault zones; this is why most veins are shaped like fault zones, a long and narrow plane. This is the process that forms nearly all gold-quartz veins.” In other instances, gold and accompanying precipitates may have filled small parallel fissures, creating a network of veins called “stockwork zones.” In still other instances, they may have filled tube-shape cavities to form “plugs.” Where the water invaded porous rock formations, “you may get a big disseminated deposit,” says Ralph.
In those instances in which the water flowed rapidly into large openings, where temperatures and pressures drop rapidly, the gold precipitated out of the solution quickly, often in the form of fine grains. When the water flowed into small openings, where temperatures and pressures fell less rapidly, the gold precipitated more slowly, as larger, if often dispersed, nuggets.
Over long periods of time, the gold, freed by erosion or disintegration of its host rock, issued into washes to be transported downstream as flakes or grains or nuggets by the flow of water. According to Prospectors Paradise, “Gold particles in stream deposits are often concentrated on or near bedrock, because they move downward during high-water periods when the entire bed load of sand, gravel, and boulders is agitated and is moving downstream. Fine gold particles collect in depressions or in pockets in sand and gravel bars where the stream current slackens. Concentrations of gold in gravel are called ‘pay streaks,’ or placers.
Although they probably did not understand the geologic processes that delivered gold to the earth’s surface, many early prospectors, often possessed by their dreams of a rich strike, knew enough to search the deformed and fractured rocks of faults, the contacts between strata, the cavities of geologic formations, the bed-rock exposures and sand and gravel bars of streams across the desert basins and mountain ranges of the Southwest.
If you are interested in prospecting for gold, you can follow in the footsteps of those early prospectors. You will likely find that the most immediately rewarding places will be possible placer deposits in the sand or gravel bars in washes downstream from known lodes. You will need no more than the simplest of the prospector’s tools—a shovel and a pan.
By Jay W. Sharp
Gold, the alchemists believed, could be made in their dark and primitive laboratories, provided they could just find the magic tincture they called “Philosopher’s Stone.” They believed that this mysterious substance could not only heal the soul, cure the sick and extend life, it could transform the lesser metals into gold. It would open the way to universal happiness. (If the alchemists failed in their search for Philosopher’s stone, they did lay the foundation for modern chemistry.)
Gold, a part of the primal stew of elements that gave birth to our planet, settled well below the surface. With the passage of time, some gold came into contact with ground water that had been heated by molten rock. If pressures were high and the geochemistry was right, the gold as well as other minerals like quartz, galena and pyrites dissolved into the water. Superheated, the water, laden with its burden of gold and other materials, surged upward, driven by pressure toward the surface. It intruded into fractures and folds of fault zones, contacts between differing rock types, openings of porous rock formations, and other cavities near the surface. As heat and pressure diminished, the water yielded back to the earth its load of gold and the companion materials, which precipitated out of solution to form veins, or lodes.
In those instances in which the water flowed rapidly into large openings, where temperatures and pressures drop rapidly, the gold precipitated out of the solution quickly, often in the form of fine grains. When the water flowed into small openings, where temperatures and pressures fell less rapidly, the gold precipitated more slowly, as larger, if often dispersed, nuggets.
Over long periods of time, the gold, freed by erosion or disintegration of its host rock, issued into washes to be transported downstream as flakes or grains or nuggets by the flow of water. According to Prospectors Paradise, “Gold particles in stream deposits are often concentrated on or near bedrock, because they move downward during high-water periods when the entire bed load of sand, gravel, and boulders is agitated and is moving downstream. Fine gold particles collect in depressions or in pockets in sand and gravel bars where the stream current slackens. Concentrations of gold in gravel are called ‘pay streaks,’ or placers.
If you are interested in prospecting for gold, you can follow in the footsteps of those early prospectors. You will likely find that the most immediately rewarding places will be possible placer deposits in the sand or gravel bars in washes downstream from known lodes. You will need no more than the simplest of the prospector’s tools—a shovel and a pan.
By Jay W. Sharp
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