Explain the formation, types, characteristics, and uses of rocks, referencing specific locations in Kenya.

a) A rock is a naturally occurring solid aggregate of one or more minerals or mineraloids.

b)

Igneous Rocks	Sedimentary Rocks	Metamorphic Rocks
Granite	Sandstone	Marble
Basalt	Limestone	Slate

c) Extrusive igneous rocks have a fine-grained or glassy texture due to rapid cooling on the Earth's surface, while intrusive igneous rocks have a coarse-grained texture with larger crystals due to slow cooling beneath the Earth's surface.

d)

• Taita Hills
• Western Kenya (e.g., around Kakamega)

e)

• Rocks are used as building and construction materials such as ballast, cement (from limestone), and dimension stones for houses and roads.
• Rocks are a source of valuable minerals and ores like gold, fluorspar, and gemstones, which are mined for economic benefit and industrial use.

f)

• Observation and description: Geographers examine rock outcrops directly, noting features like color, texture, layering, mineral composition, and the presence of fossils. This helps in initial classification and understanding the rock's origin.
• Sampling: Geographers collect small, representative rock samples using tools like a geological hammer. These samples are then taken to a laboratory for detailed analysis, such as thin section microscopy or chemical analysis, to determine precise mineralogy and composition.

g)

• Limestone $\rightarrow$ Marble
• Shale $\rightarrow$ Slate
• Sandstone $\rightarrow$ Quartzite