I am the metal that is more valuable than gold or silver.

A type of rock formed when magma solidifies.

The branch of geology that deals with the identification and classification of minerals.

A horizontal rock layer that has a different type of rock layer above it.

I am a porous, lightweight structure containing millions of tiny bubbles that is so light that it floats in water.

A type of rock formed when deposits of sand and mineral fragments are cemented together.

Substances that exist naturally in the earth's crust as single, uncombined elements and are the smallest group of minerals.

Rock that consists of smooth pebbles embedded in hardened sand or clay.

I am a well-known chemical sedimentary rock, of which 50% consists of calcium carbonate.

Rocks that have a smooth, glasslike texture.

Substances that are found naturally in the earth and have a crystalline structure.

Chemical sediments that result from the evaporation of water.

I am a course-grained igneous rock that is usually found in massive formations and composes most of the earth's continental crust.

Rocks made up of layers like the leaves of a book.

Geometric structures that are composed of atoms or molecules and have an orderly arrangement.

Minerals that continue to glow for a while after being exposed to ultraviolet light and then placed in the dark.

I am the most common sedimentary rock.

A type of rock formed when preexisting rocks are altered by heat or pressure.

The largest group of minerals, which compose over 90% of the earth's crust.

Hard, round structures that form when minerals settle out of water and crystalize around a sand grain or other mineral fragment.