W e love collecting rocks. When we return from somewhere our pockets are usually full with things we have picked up. We don't always know what kinds of rocks we have found, but we find it a rewarding family activity to collect and catalog them. We also frequent rock stores, and we have most of the standard items you would find on the shelves. The rock images used for bullets and buttons in our Web pages were all scanned in from our collection.
Rocks are natural aggregates or combinations of one or more minerals.
They are usually classified into three main types. Igneous rocks form within the earth by crystallization of molten magma. Sedimentary rocks form at the bottom of lakes and oceans from minerals and grains of other rocks that settle there. Metamorphic rocks may be igneous or sedimentary in origin, but they have been altered into new states by extreme pressure or temperature. These both have high-quality photographs and excellent text descriptions to help you figure out what you are looking at.