Select the one substance that is not a mineral.

 - Gypsum is a solid. It is not made by living things.
 - Native gold is a pure substance. It is not made by living things.
 - Brass is made in a factory. 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.
Native gold is a mineral.
Gypsum is a mineral.
Brass is made in a factory. But all minerals are formed in nature.
So, brass is not a mineral.