Select the one substance that is not a mineral.

 - Soap is made in a factory. It is not a pure substance.
 - Sphalerite is a pure substance. It is not made by living things.
 - Hematite is not made by living things. It is a solid.
Compare the properties of each substance to the properties of minerals. Select the substance whose properties do not match those of minerals.
Hematite is a mineral.
Sphalerite is a mineral.
Soap is made in a factory. But all minerals are formed in nature.
Soap is not a pure substance. But all minerals are pure substances.
So, soap is not a mineral.