Question

Which of the following statements are incorrect with regard to Placer deposits?
They occur as alluvial deposits
ii. They are corroded by water
ill. They occur in ocean beds
They are found in sands of valley floor and base of hills
a) Statements (i) and (ii)
b) Statements (iii) and (iv)
c) Statements (ii) and (ii)
d) Statements (i) and (iv)
iv.​

Answer 1

(ii) They are corroded by water.

(iii) They occur in ocean beds are incorrect with regard to Placer deposits

Option: (b)

Explanation:

• A placer deposit or placer is an aggregation of precious minerals produced through gravity separation from a particular source rock at the time of  sedimentary processes. .Types of placer deposits include alluvium (alluvial) ( (transported through a river), eluvium, colluvial (transported through gravity action) beach placers (coarse sand deposited along the edge of large water bodies)), and paleoplacers (ancient buried and converted rock from an original loose mass of sediment)
• Typical places for alluvial golden placer deposits are situated inside the curves of the rivers, and in the streams' break of slope; natural sloping areas; he base of an escarpment or a rift, waterfall and other barrier. These deposits are called ‘placer deposits’ and comprise minerals, that whichare not corroded by water.
• Minerals which form from placer deposits have high specific gravity, are chemically resistant to weathering, and are durable; such minerals comprise platinum, gold, chromite, cassiterite, native copper, magnetite, ilmenite, rutile, monazite,  zircon, and various gemstones.