This is the Navajo Sandstone, a huge layer of rock that forms the cliff in our back yard. The strange patterns in the sandstone tell us that at the time they were formed, this area was a desert, and the sand formed sand dunes. What kind of rock is sandstone?

1. Igneous

   No. Igneous rocks are formed from molten lava or magma, not from sand.

2. Sedimentary

   Yes! Sedimentary rocks are made up of bits of other rocks that have been deposited by wind, water, ice, or gravity. This sand was deposited by the wind, making this a sedimentary rock.

3. Metamorphic

   No. Metamorphic rocks have been changed by heat and/or pressure. If this sandstone was exposed to tremendous heat and pressure, it could change into a metamorphic rock called quartzite.

4. Sandstone is not a rock.

   No. Sandstone is a naturally occurring solid that forms large layers in the Earth. It is a rock.

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