User: How are rocks formed?
Assistant: Rocks are formed from molten rock from volcanos.  When the lava cools new earth is formed after it solidifies.  Sediment rocks are forms when particles in the air settle because of rain, or when minerals from water gather and cause mineral scale.  You also get rocks when layers of earth (e.g. dirt) build on top of each other and compress the layers beneath it for millions of years.