TOM THE ATOM, BOOK 11
A Day at the museum: Mary and her friends discover the Earth’s crust and its material!
GOAL: Mary and her classmates visited an exhibit on the Earth’s crust at the Lawrence Hall of Science at Berkeley to see the exhibition on Rocks.
In the Earth crust, we find Minerals (the same type of atomic-compounds, usually forming pretty crystals), Rocks (a combination of two or more minerals), and Metallic-Ores (collection of pure Metal atoms held together by Metallic or covalent bonds or metals combined with non-metals). Students become geologists (who study rocks) as they explore the properties and characteristics of several types of stones.
Minerals are made of either a single chemical element or a combination of chemical elements that repeat throughout. They have a crystalline structure (Crystals). Covalent and ionic bonds between atoms are the most common atomic bonds among minerals. In minerals, in contrast to the metals, the atoms tightly hold their valence electrons. Accordingly, most minerals are insulators. A rock is a combination of two or more minerals.
They are not always crystalline (can also contain organic remains and metallic formations). Metals-Ores are minerals containing enough metal to allow for the economic extraction of the metal.