What is a placer deposit?

What is a placer deposit?

What is a placer deposit?

“Placer” deposits are formed by surface weathering and ocean, river or wind action resulting in concentration of some valuable heavy resistant minerals of economic quantities. The placer can be an accumulation of valuable minerals formed by gravity separation during sedimentary processes.

What do you mean by placer deposits Class 10?

What are ‘placer deposits’? Answer: Certain minerals may occur as alluvial deposits in sands of valley floors and the base of hills. The deposits are called ‘placer deposits’, and generally contain minerals, which are not corroded by water. Gold, silver, tin and platinum are the most important among such minerals.

What is a placer deposit quizlet?

What is placer deposit? An accumulation of minerals that have formed from gravity separation; occurs in sedimentary processes.

How do placer deposits form quizlet?

Placer deposits are formed by flowing water, e.g. streams or along coasts. As the water velocity slows down, e.g. at a point bar in a stream, minerals may, over time, settle out and accumulate in these regions.

What are placer deposits give examples of such deposits?

i Certain minerals may occur as alluvial deposits in sands of valley floors and base of hills. These deposits are called placer deposits. ii They generally contain minerals which are not corroded by water. iii Gold silver tin and platinum are examples of some important minerals found in placer deposits.

What are called placer deposits name some minerals obtained from placer deposits?

How does a placer deposit form?

Formation of Placers Placer deposits consist of minerals broken off by weathering from the rocks in which they formed, and subsequently concentrated by gravity aided by a winnowing or sifting process. The source of the mechanical energy required for the sifting includes streams or rivers, ocean waves, wind or glaciers.

What are two places where placer deposits commonly form?

Examples of stream placers include the rich gold deposits of Alaska and the Klondike, the platinum placers of the Urals, the tin (cassiterite) deposits of Malaysia, Thailand, and Indonesia, and the diamond placers of Congo (Kinshasa) and Angola. Eluvial placers form on hillslopes from weathered deposits.

How ore deposits are formed?

Deposits of minerals form when a medium that contains and transports mineral-making ore releases and deposits the ore. Magma is one such medium that transports ores. When magma or lava cools, the magma and ore carried within it crystallize to form tiny minerals in the newly-created igneous rock.