Describe the three rock types and the rock cycle that connects them, and identify real uses of common rocks and minerals as resources.
A mineral is a naturally occurring, non-living solid with a specific chemical makeup and crystal structure, like quartz or salt; a rock is simply a solid mass made of one or more minerals mixed together. Rocks fall into three types based on how they formed: igneous rock forms when hot, molten rock, magma or lava, cools and hardens; sedimentary rock forms when layers of sediment, sand, mud, shell fragments, get pressed and cemented together over time; and metamorphic rock forms when heat and pressure inside Earth transform an existing rock into a new one without fully melting it.
These three rock types are not a one-way street; they are connected in a continuous rock cycle. Over long periods of time, any rock type can be broken down, buried, heated, or pressured into becoming a different type. Rocks and minerals are also everyday resources: granite and marble are used in countertops and buildings, limestone is a key ingredient in cement, and metal ores, rock containing enough of a metal like copper or iron to be worth mining, supply the materials in wiring, tools, and vehicles.
Mastery looks like: They can name the three rock types with how each forms, describe the rock cycle as connecting them, and name a real resource use for at least one rock or mineral.
Common stumbles: Thinking the rock cycle only moves in one direction; confusing "mineral" and "rock" as interchangeable words.