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Choose one of the following Rocks for more details:

Aluminum Cube

Aluminum Cube

This 546 gram cube represents the amount of aluminum in bauxite (catalog number 162044) and granite (catalog number 116626-3). There is much more granite than bauxite in Earth's crust. But only bauxite is the ore. Why? Aluminum is far more easily and cheaply extracted from bauxite than from granite. Lightweight and corrosion resistant, aluminum is used for making cars and buildings, packaging materials, and aircraft.

Aluminum Pyramid

Aluminum Pyramid

This pyramid, 2,835 grams (100 oz), is an exact replica of the aluminum cap set atop the Washington Monument in 1884.

Asphalt

Asphalt

Asphalt is a tarlike hydrocarbon mixture that is solid or semisolid at room temperature. It is heated and combined with aggregate (crushed stone, or sand and gravel) to form the familiar material that paves most roads. Most asphalt is made by evaporating crude oil.

Concrete

Concrete

The ancient Egyptians, Greeks, and Romans all used concrete, a synthetic rock made of aggregate (crushed stone, or sand and gravel). Heating limestone, clay, and silica to 1,425°C (2,600°F) makes cement, the glue in concrete. Combining cement, aggregate, and water forms concrete.


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