Minerals

1. geologists

1.1. Geologists study Minerals

2. properties

2.1. hardness

2.1.1. Mohs Hardness Scale

2.1.1.1. Talc (softest)

2.1.1.1.1. Gypsum

2.2. color

2.3. crystalline

2.4. fluorite

2.5. Rocks

2.5.1. geologists study rocks

2.6. diamonds

3. Rocks

3.1. Sedimemtary

3.2. Metamorfic

3.3. Igneous