Schools Science Clips - Rocks and soils

Geology.com: Rocks Lapis Lazuli Lapis Lazuli - a metamorphic rock and the most popular blue opaque gemstone in history. Tumbled Stones Tumbled Stones are rocks that have been rounded, smoothed and polished in a rock tumbler. Quartzite Quartzite a nonfoliated metamorphic rock composed almost entirely of quartz. Fluorescent Minerals Fluorescent Minerals and rocks glow with spectacular colors under ultraviolet light. Geology.com Store Gifts that Rock! Geodes Geodes look like ordinary rocks on the outside but can be spectacular inside! Trap Rock Trap Rock is a name applied to any dark-colored igneous rock used to produce crushed stone. Don*t Go To Jail Rock Collectors must know the rules before removing rocks from public and private property. Difficult Rocks Difficult Rocks Elementary students find lots of rocks that you will not be able to identify. Sand Grains A Grain of Sand Gallery of sand grains through a microscope by Dr. Sand Sand is a diverse material. Shale Siltstone Rock Tumbling Soapstone Rock Art Unakite Crushed Stone

National Geographic: Minerals, Gems Information More than 4,000 naturally occurring minerals—inorganic solids that have a characteristic chemical composition and specific crystal structure—have been found on Earth. They are formed of simple molecules or individual elements arranged in repeating chains, sheets, or three-dimensional arrays. Minerals are typically formed when molten rock, or magma, cools, or by separating out of mineral-rich water, such as that in underground caverns. In general, mineral particles are small, having formed within confined areas such as lava flows or between grains of sediments. Large crystals found in geodes and other rocks are relatively rare. Rocks themselves are made of clusters or mixtures of minerals, and minerals and rocks affect landform development and form natural resources such as gold, tin, iron, marble, and granite. Silicates—including quartz, mica, olivine, and precious minerals such as emeralds—are the most common class of minerals, as well as the major components of most rocks. Gemstones