Igneous rock forming minerals

Question 1

Examples of common and accessory igneous minerals:

Answer 1

• Common igneous minerals: Plagioclase feldspar, potassium feldspar, quartz, pyroxenes (such as enstatite and augite), hornblende, muscovite, biotite, olivine.
• Accessory igneous minerals: Magnetite, ilmenite, pyrite, pyrrhotite, chalcopyrite, apatite, zircon.

Question 2

Examples of igneous minerals used as materials:

Answer 2

• Plagioclase feldspar: Used for concrete, asphalt-based pavement, paint, plastic, rubber, glass, and ceramics.
• Potassium feldspars: Used as a flux in ceramic mixtures, in glass making, enamel and glaze formulations, and cleaning compounds.
• Quartz: Used in glass making, ceramics, foundry sand, and high purity quartz is in demand for silicon chips and solar cells.
• Olivine: Used as foundry sand for shaping metals, in iron/steel making, making refractories, and sandblasting.
• Ilmenite: Major ore for titanium used in aircraft, artificial joints, bicycles, paint, plastics, and pigment production.

Question 3

Examples of mineral formulas:

Answer 3

Quartz: SiO2.
Magnetite: Fe3O4.
Ilmenite: FeTiO3.
Pyrite: FeS2.
Chalcopyrite: CuFeS2.
Zircon: ZrSiO4.