Mineralogy Basics

Study Notes

Definition and Classification

Minerals are naturally occurring inorganic substances with a specific chemical composition and a crystalline structure.
Classified into different groups based on their chemical composition and properties.

Types of Minerals

Oxides: Minerals with oxygen as the anion, e.g., hematite (Fe2O3), magnetite (Fe3O4).
Silicates: Minerals with silicon and oxygen as the main components, e.g., quartz (SiO2), feldspar (KAlSi3O8 – NaAlSi3O8 – CaAlSi3O8).
Carbonates: Minerals with carbon and oxygen as the anion, e.g., calcite (CaCO3), dolomite (CaMg(CO3)2).
Sulfides: Minerals with sulfur as the anion, e.g., pyrite (FeS2), galena (PbS).
Halides: Minerals with chlorine, bromine, or iodine as the anion, e.g., halite (NaCl), sylvite (KCl).
Native Elements: Minerals composed of a single element, e.g., gold (Au), copper (Cu), sulfur (S).
Phosphates: Minerals with phosphorus and oxygen as the anion, e.g., apatite (Ca5(PO4)3(F,Cl,OH)).

Physical Properties

Color: Minerals can have a wide range of colors, from transparent to opaque.
Luster: The way a mineral reflects light, e.g., metallic, glassy, earthy.
Streak: The color of the powder produced when a mineral is scratched on a porcelain plate.
Hardness: A mineral's resistance to scratching, measured on the Mohs hardness scale (1-10).
Cleavage: The way a mineral breaks or splits along flat surfaces.
Fracture: The way a mineral breaks or splits in a non-flat surface.
Density: A mineral's mass per unit volume.

Chemical Properties

Chemical Composition: The proportion of elements that make up a mineral.
Reactivity: The ability of a mineral to react with other substances, e.g., acids, water.
Solubility: The ability of a mineral to dissolve in a solvent.

Uses of Minerals

Construction: Minerals used in building materials, e.g., limestone, sand, gravel.
Manufacturing: Minerals used in the production of goods, e.g., iron, copper, chromium.
Electronics: Minerals used in electronic devices, e.g., copper, silver, gold.
Agriculture: Minerals used as fertilizers, e.g., potassium, phosphorus.
Jewelry and Decorative Items: Minerals used in the production of gemstones, e.g., diamonds, rubies, emeralds.

Description

Test your knowledge about minerals, including their definition, classification, types, physical and chemical properties, and uses. Learn about the different categories of minerals, their characteristics, and applications.