Minerals and Ores

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

Metallurgy is the branch of science and technology concerned with the properties of metals and their production and purification.

Density is defined as the amount of mass (matter) per unit volume. It is a physical property that helps identify minerals.

The Mohs Scale of Mineral Hardness is the standard scientific tool used to characterize the scratch resistance of various minerals.

Minerals are broadly categorized into silicates (containing silicon and oxygen) and non-silicates (which do not contain the silicon-oxygen tetrahedron).

Minerals are primarily classified based on their chemical composition, specifically the anions or anionic groups they contain.

Natural rubber is harvested as latex from the sap of specific tropical trees, most notably the Hevea brasiliensis tree.

The United States possesses the world's largest proven coal reserves, accounting for a significant portion of the global total. This is due to the vast swampy environments that existed in North America during the Carboniferous period.

The continental crust is primarily composed of silica and alumina, which is abbreviated as 'sial' (Si for silica and Al for alumina). The oceanic crust, on the other hand, is called 'sima' because it consists mainly of silica and magnesium.

Color is the least reliable property because many minerals come in a variety of colors due to minor impurities, and different minerals can share the same color. Properties like hardness, streak, and luster are much more consistent and reliable for identification.

Minerals are inorganic substances because they do not contain carbon-hydrogen bonds and originate from non-living sources like soil and water. Organic compounds, by contrast, are carbon-based molecules typically produced by living organisms.

Limestone is a sedimentary rock composed primarily of calcium carbonate. It is classified as a non-metallic mineral resource.

Moh's scale is a qualitative ordinal scale characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material.

Coal is considered an economic mineral resource because it is valuable, in high demand, and can be extracted profitably to serve societal energy needs.

Minerals are finite resources that take millions of years to form. Once extracted and used, they cannot be replaced on a human timescale, making them exhaustible, not inexhaustible.