Page 9 - Curriculum Visions Dynamic Book
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For more on gold, see Volume 5: Copper, Silver, and Gold in the Elements set.
Geology
It is found widely in pure native form in veins close to ancient volcanoes.
It also appears in rivers, where it
was traditionally recovered by panning. Most of the river gold (called placer gold) comes in
small pieces, but sometimes large nuggets do occur.
The fact that it could be found so easily, and that it is soft and does
๎ A gold nugget and flakes. Each flake is about 3mm long.
๎ Panning for gold on the Klondike River in Canada.
๎ A Krugerrand, one of the worldโs most famous gold coins.
not corrode, explains why it was one of the first metals ever used by people. However, all the gold in the world that has so far been refined would still only make up a cube with a 20m/60ft side.
Gold is now extracted from ores in which the gold content is tiny, and the huge volumes crushed can cause wide environmental damage.
Biology
Gold is not naturally found in the body, but it has been used to treat rheumatoid arthritis.
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