This is Dolostone, she is a sedimentary rock. Sedimentary rocks are formed through the process of weathering and erosion. First deposition (erosion) take sediments to a location to add to the landscape. Then the grains are smooshed together and stay together. This is how sedimentary rocks are made.
This is Gabbro, he is a igneous rock. Igneous rocks form from volcanoes and go through the process of melting and solidification. Gabbro a unique rock because magma was used to create him and he is denser than other rocks. Magma is created by melted rock from the earth's mantle that lies underneath the crust.
This is Slate. Slate is a metamorphic rock. Metamorphic rocks are like hybrids because they can come from igneous rocks and sedimentary rocks. Slate was created by a process called metamorphism. Metamorphic rocks go through metamorphism because of pressure and heat.
One day the metamorphic rocks found a new place and claimed it so it can be their new home. Their old home was overpopulated, so they had no choice. After a couple of months they settled down and relax for a long time. But they should have known that peace doesn't last forever.
Years later, the igneous rocks invaded and took over. Then the sedimentary rocks came in and fought, so they can give the land back to the metamorphic rocks, because they always had their back. But the sedimentary were out numbered, so they had to flee.
The sedimentary rocks told the metamorphic rocks what happened. After a great long talk the two types of rocks joined forces, so that one day the metamorphic rocks can take back their land and became best friends.