History
Placers supplied most of the gold for a large part of the ancient world. Hydraulic mining methods such as hushing were used widely by the Romans across their empire, but especially in the gold fields of northern Spain after its conquest by Augustus in 25 BC. One of the largest sites was at Las Médulas, where seven 30 mile long aqueducts were used to work the alluvial gold deposits through the first century AD. (Inclusions of platinum-group metals in a very large proportion of gold items indicate that the gold was largely derived from placer or alluvial deposits. Platinum group metals are seldom found with gold in hardrock reef or vein deposits.) In North America, placer mining was famous in the context of several gold rushes, particularly the California Gold Rush, the Fraser Canyon Gold Rush and the Klondike Gold Rush. Placer mining continues in many areas of the world as a source of diamonds, industrial minerals and metals, gems (in Myanmar and Sri Lanka), platinum, and of gold (in the Yukon, Alaska and British Columbia).
Read more about this topic: Placer Mining
Famous quotes containing the word history:
“[Men say:] “Don’t you know that we are your natural protectors?” But what is a woman afraid of on a lonely road after dark? The bears and wolves are all gone; there is nothing to be afraid of now but our natural protectors.”
—Frances A. Griffin, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4, ch. 19, by Susan B. Anthony and Ida Husted Harper (1902)
“A poet’s object is not to tell what actually happened but what could or would happen either probably or inevitably.... For this reason poetry is something more scientific and serious than history, because poetry tends to give general truths while history gives particular facts.”
—Aristotle (384–323 B.C.)
“Look through the whole history of countries professing the Romish religion, and you will uniformly find the leaven of this besetting and accursed principle of action—that the end will sanction any means.”
—Samuel Taylor Coleridge (1772–1834)