Mineral
A mineral is a naturally occurring, inorganic, crystalline solid with a definite chemical composition and characteristic physical properties. Minerals are the building blocks of rocks and are classified by their crystal structure, hardness, luster, cleavage, and color. They are essential to industry, construction, and biological processes, with over 5,000 known mineral species recognized by the International Mineralogical Association.
Common Rock-Forming Minerals and Their Properties
| Mineral | Chemical Formula | Hardness (Mohs) | Luster | Common Use |
|---|---|---|---|---|
| Quartz | SiO₂ | 7 | Vitreous | Glass, electronics |
| Feldspar | KAlSi₃O₈ | 6 | Vitreous/pearly | Ceramics, glass |
| Calcite | CaCO₃ | 3 | Vitreous | Cement, lime |
| Mica (Muscovite) | KAl₂(Si₃Al)O₁₀(OH)₂ | 2–3 | Pearly/silky | Electrical insulation |
| Pyrite | FeS₂ | 6–6.5 | Metallic | Sulfur production |
| Halite | NaCl | 2.5 | Vitreous | Table salt, food preservation |
Interactive Tools
Mineral Identification Tool — Mindat.org
Comprehensive mineral database with photos, properties, and locality data for over 5,000 minerals.
Open ToolKhan Academy — Minerals and Rocks
Video lessons on mineral identification, properties, and classification.
Open ToolWolfram Alpha — Chemical Mineral Lookup
Query mineral chemical formulas, crystal systems, and physical constants.
Open Tool
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Related Terms
Rock Cycle
The rock cycle is a continuous geological process by which rocks are transformed from one type to another through processes such as melting, cooling, erosion, deposition, compaction, cementation, heat, and pressure over geological timescales. The three main rock types — igneous, sedimentary, and metamorphic — are interconnected in this cycle, each capable of being converted into another type under the right conditions. Understanding the rock cycle helps geologists interpret Earth's history, locate mineral resources, and predict geological hazards.
Weathering (Geology)
Weathering is the in-situ breakdown of rocks and minerals at or near Earth's surface through physical disintegration, chemical decomposition, and biological activity, without significant transport of the resulting material. Physical (mechanical) weathering fragments rock into smaller pieces without changing its mineral composition, while chemical weathering alters mineral chemistry through reactions with water, oxygen, and acids. Biological weathering involves living organisms such as plant roots, lichens, and bacteria accelerating both physical and chemical breakdown processes.
Soil Formation
Soil formation (pedogenesis) is the process by which parent rock material is transformed into soil through the combined effects of weathering, biological activity, organic matter accumulation, and the movement of water and dissolved substances through the soil profile. The CLORPT model identifies five key soil-forming factors: climate, organisms, relief (topography), parent material, and time. The result is a layered soil profile with distinct horizons—O, A, B, C, and R—each reflecting the degree of weathering, organic content, and mineral alteration at different depths.
From Latin "minerale" (ore, mine product), derived from "minera" (mine), which traces to Old French "miniere." The systematic scientific study of minerals was established by René Just Haüy in the late 18th century, who is considered the father of crystallography.