Diamond is a valuable gemstone but not a common rock-forming mineral due to its rarity and specific formation conditions.

The Mohs scale is a measure of a mineral's resistance to scratching, with harder minerals able to scratch softer ones.

Igneous rocks are formed from the cooling and solidification of molten rock, either above or below the Earth's surface.

Sedimentary rocks are formed through a combination of erosion, weathering, compaction, and cementation of sediments.

Metamorphic rocks are formed when existing rocks are subjected to high temperatures and pressures, causing changes in their mineral composition and texture.

Foliation is the term for the flat, sheet-like structure found in some metamorphic rocks, resulting from the alignment of minerals during metamorphism.

Feldspar is a common mineral found in granite, along with quartz and mica, contributing to its characteristic texture and composition.

Weathering is the process by which rocks break down into smaller pieces due to exposure to the elements, such as wind, water, and temperature changes.

Coal is a sedimentary rock formed from the accumulation and compaction of organic matter, primarily plant material, over millions of years.

Crystallization is the process by which minerals crystallize from a molten or dissolved state, resulting in the formation of solid crystals with a regular arrangement of atoms.

Pyroxene is a common mineral found in basalt, along with olivine, contributing to its dark color and fine-grained texture.

Lithification is the process by which sedimentary rocks are formed from the accumulation and compaction of sediments, resulting in the formation of solid rock.

Sandstone is a sedimentary rock formed from the accumulation and compaction of sand, consisting primarily of quartz grains.

Erosion is the process by which rocks are broken down into smaller pieces by physical forces, such as wind, water, and ice.

Calcite is a common mineral found in limestone, contributing to its characteristic white or gray color and its use in the production of cement.