2007-01-13 06:57:35 · 8 answers · asked by leztew 1 in Science & Mathematics ➔ Earth Sciences & Geology
Alluvial or placer gold is gold that is found ‘loose’ on this planet, usually in the form of pieces as fine as flour up to nuggets weighing a few grams or, very rarely, up to a few pounds. This is raw, native gold that was long ago loosened from the ore which once contained it, usually by the action of wind and water. Placer gold has been our traditional source of gold over the millennia. Deep mining, which is responsible for South Africa’s vast gold production today, wasn’t started until the late 1800’s.
Placer gold is often found in streambeds, both flowing and dry. Its rounded shapes are the products of thousands or millions of years of weathering. Most placer gold as it comes from the ground is 70% to 95% pure gold, depending on where its found.
Here in Arizona, quite a bit of alluvial gold has been mined over the years. The earliest Anglo settlements in Arizona were established in the 1860’s near the gold diggings around what is now Prescott. Gold and copper mining were the impetus to early settlers in Arizona, bringing first the Spanish and then the English, Chinese, and various European expatriates, many of whom were fresh off a stint in the California gold fields in the early 1850’s.
Today in Arizona there are still some profitable smaller-size gold mines, and gold and silver are by-products of this state’s huge copper pit-mining operations. Many commercial gravel dredge operations here yield their owners a bit of gold. Most sunny weekends bring out the gold panners, sluice operators, and treasure hunters wielding metal detectors, each out in Arizona’s vast remote areas of desert and forest, looking to add a bit of color to his or her poke
2007-01-13 07:05:48 · answer #1 · answered by e3456 4 · 2⤊ 0⤋
A rock dosen't carry gold. what carries gold is a gold ore you can usually find them under ground but it wont matter much because you have to do a process to take the gold out. hope i helped
2007-01-13 07:02:53 · answer #2 · answered by Manderin J 2 · 0⤊ 2⤋
The kind of rocks that are in gold-mines.
2007-01-13 06:59:41 · answer #3 · answered by Anpadh 6 · 0⤊ 3⤋
Igneous rocks.
Quartz is a common source.
2007-01-13 07:01:18 · answer #4 · answered by The answer guy 3 · 0⤊ 0⤋
Often found in quartz veins... some locally also associated with arsenic, so no one is allowed to mine it (pollution concerns)...
2007-01-13 07:00:44 · answer #5 · answered by waynebudd 6 · 0⤊ 1⤋
I know quartz bearing granite does.
2007-01-17 06:18:16 · answer #6 · answered by Laura Marie B 3 · 0⤊ 0⤋
igneouis
2007-01-13 07:05:44 · answer #7 · answered by Paula S 2 · 0⤊ 0⤋
quorts
2007-01-13 07:00:27 · answer #8 · answered by TEBOE7 3 · 0⤊ 0⤋