Select the one substance that is not a rock.
Chert is not a pure substance. It is a solid. Calcarenite is formed in nature. It is a solid. Burlap is made by humans. It is a solid.
Rocks are made of minerals. Here are some properties of rocks:
They are solid.
They are formed in nature.
They are not made by living things.
They are not pure substances.
Compare the properties of each substance to the properties of rocks. Select the substance whose properties do not match those of rocks.
Calcarenite is a rock.
Burlap is made by humans. But rocks are not made by living things.
So, burlap is not a rock.
Chert is a rock.