You're asking about the composition of the three main rock types: igneous, sedimentary, and metamorphic. Here's a breakdown:

Igneous Rocks

* Made of: Minerals that crystallize from molten rock (magma or lava).

* Examples: Granite, basalt, obsidian

Sedimentary Rocks

* Made of: Weathered and eroded fragments of existing rocks (sediments), minerals, and organic matter. These fragments are cemented together over time.

* Examples: Sandstone, limestone, shale

Metamorphic Rocks

* Made of: Existing igneous, sedimentary, or even other metamorphic rocks that have been transformed by heat, pressure, or chemical reactions.

* Examples: Marble, slate, gneiss

In Summary

All three rock types are fundamentally composed of minerals. The key difference lies in how they form:

* Igneous: Crystallization from molten rock.

* Sedimentary: Cementation of weathered fragments.

* Metamorphic: Transformation of existing rocks by heat, pressure, or chemical processes.