Question

Which out of these are classified as non-metallic minerals?
A. Rubies
B. Diamonds
C. Gold
D. Copper

Answer 1

Hint: The minerals that lack metallic characteristics like that of being good electric and thermal conductivity, luster, rigour and malleability. This non-metallic mineral is very much useful in many industries.

Complete answer: Option A- Rubies are aluminium oxide and non-metallic minerals. It is a gem corundum with a dominant red colour. It exhibits physical properties like hardness, high specific gravity, hexagonal crystals sometimes tapering to a pyramid, luster and has conchoidal fracture. Rubies are gemstone and are extensively used in jewellery making purposes.
Option B- Diamonds are non-metallic minerals. It is a solid form of carbon element with its atoms arranged in a crystal structure. Diamond is the hardest mineral and thermal conductivity. They are generally colourless, sometimes yellow, brown or grey of crystal texture. Diamond is a gemstone and therefore is used extensively in jewellery making. Industrial abrasives, diamond windows, speaker domes, heat sinks, low-friction micro bearings, and others are other important utilities of diamond.
Option C- Gold is a transition metal, that is, it is in a state in between of solid and liquid. It is one of the least reactive metals. It gets solid under certain standard conditions. It has a metallic yellow colour. Jewellery making is the main utility of this transition metal. It is a very good reflector so is used in artificial satellites, infrared protective faceplates and others.
Option D- Copper is a metallic mineral and is very much used in industrial purposes. It has high ductility, malleability, thermal and electrical conductivity and has the ability to resist corrosion. It is used in the making of utensils, for creating connectivity through wires, helps to make alloys easily, and many others.

Therefore, from the above discussion it can be said that both options A and B, that is rubies and diamonds, are the correct answers.

Note: The hardness, sparkle, luster of the diamonds make them the most valued jewel. Diamonds are generally found in three types of deposits, which are alluvial gravels, glacial tilts and kimberlite pipes. They vary from colourless to black in colour and can be transparent, translucent or opaque. The colour of rubies becomes red ultraviolet fluorescence under the influence of longwave. Rubies can be found in the countries like Sri lanka, Thailand, Myanmar, Brazil, Scotland, Cambodia, Japan, Vietnam, Tanzania, and many others.