Presentation on theme: "What is a Mineral pages 103-114 the building blocks of rocks Minerals of Earth’s Crust."— Presentation transcript:
What is a Mineral pages the building blocks of rocks Minerals of Earth’s Crust
Mineral definition A mineral is a natural, usually inorganic solid that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties.
Five characteristics naturally formed inorganic crystalline structure solid definite chemical composition
Naturally Formed Not man made, naturally occurring
Inorganic Organic means living so, this means non-living
Crystalline structure The atoms are arranged in a pattern that repeats over and over
Solid Definite volume and shape Not a liquid or gas
Definite Chemical Composition Its chemical composition may be written down in a formula and is fairly consistent or within a range Example:chemical composition Halite (salt) NaCl Galena (lead) Pb
Kinds of Minerals More than 4,000 have been identified Fewer than 20 are common These are called rock-forming minerals
These ten make up 90% of the crust Quartz Orthoclase Plagioclase Muscovite Biotite Calcite Dolomite Halite Gypsum Ferromagnesian minerals
Ferromagnesian mineral Contain iron and magnesium
Two groups of minerals Based on chemical composition Silicates Non-silicates--
Silicates — contain a combination of Silicon, Si Oxygen, O Silicates make up more than 90% of the Earth’s crust
Six Kinds of Silicate Mineral Arrangements Isolated-do not link with other silicon or oxygen atoms Ring silicates—form rings by sharing oxygen atoms Single-chain silicates—form by sharing oxygen atoms Double chain silicates—form when two single chains of tetrahedra bond to each other Sheet silicates—form when each tetrahedron shares three of its oxygen with other tetrahedra Framework silicates—form when each tetrahedron is bonded to four other tetrahedra
Nonsilicates 5 groups Carbonates Halides Native elements Oxides Sulfates Sulfides
From page 105 Write name of group Composition do not fail to write it all! An example of a mineral form each group
Hardness of some common objects 2.5 Fingernail 3 Penny 5 Pocket Knife 5.5 Window Glass 7Steel File
Cleavage The tendency of a mineral to break along planes of weakness. Some have good cleavage, some poor. It depends on the crystal structure and chemical bonds: the stronger the bond the poorer the cleavage.
Fracture A break that is not along a cleavage plane Common type is conchoidal fracture. Ex. Quartz Broken glass appearance Or can be splinters and fibers--asbestos
Luster The way light reflects from the surface I. Metallic II. Nonmetallic a. Greasy b. Silky c. Pearly d. Glassy
Color Color is good for a few minerals like copper and turquoise, but is not a very reliable means of identification. The majority of minerals appear in a variety of colors. Impurities can change the color.
Streak The color of the powdered mineral Much more reliable. Drag the mineral across a streak plate. Hematite--reddish brown to black, but usually reddish brown Limonite--yellowish brown
Specific Gravity A mineral’s density d=m/v Density = mass/volume Densities are compared to an equal volume of water There is no unit Quartz Silver Gold
Other Tests Taste Halite--NaCl has a salty taste
Fizz If a mineral contains CO 3 it will effervesce (fizz) when you drop dilute HCl (hydrochloric acid) on it. Ex. Calcite CaCO 3
Feel Talc has a soapy feel
Smell Sulfur has a rotten egg smell Kaolinite has an earthy smell
Etc Writes on paper--graphite Rusty look—limonite
How to Identify Minerals This film reviews some of the tests covered in your notes.
Mineral Lab Test each of the minerals to determine their physical properties, and then identify them using the chart. Fill this in well. This is a major grade.