WHAT IS A MINERAL? • Naturally occurring • Inorganic • Solid • Crystalline structure • Specific physical and chemical properties
CRYSTALLINE(molecular structure) Amethyst
HOW DO MINERALS AND ROCKS DIFFER? green Olivine mineral in igneous basalt rock clear Quartz mineral
WHAT ARE MINERALS MADE OF? Minerals are made up of atoms of elements HOW MANY DIFFERENT TYPES OF MINERALS ARE THERE? There are over 3000+ different types of minerals on Earth – most minerals are “silicate” minerals (made up of silicon & oxygen) WHAT OTHER KINDS OF MINERALS ARE THERE? Carbonates, Sulfides, and Iron Oxides
HOW DO MINERALS FORM? • 2 main ways that new mineral crystals grow: • Some minerals form when molten rockbelow a planet’s surface (magma) or above (lava), coolsand atoms bondtogether into mineral crystals • Other minerals form when water that has atoms of dissolved elements in it, evaporates away-- the atoms get very close to each other and bond together to form solid minerals
HOW DO YOU IDENTIFY MINERALS? • Luster (metallic or non-metallic) • Hardness (hard or soft) • Cleavage / Fracture (way the mineral splits) • Streak (powder color of mineral)
COLOR IS LEAST RELIABLE IDENTIFICATION TEST 3 crystals of quartz mineral show how the same mineral can have different colors!
ESRT – Page 16 KNOW THIS PAGE!!!
WHY DO FLUORSECENT MINERALS GLOW IN THE DARK? Fluorescence is a physical process. For a mineral to fluoresce, ultraviolet (UV) light (electromagnetic radiation) of one wavelength strikes a fluorescent mineral and “activates” it, that causes light to come out of that mineral at another longer wavelength. When those wavelengths reach the “visible spectrum”, we see the different wavelengths as different BRIGHT colors. Fluorite Mineral Electromagnetic Spectrum
Calcite video of time decay of mineral fluorescence