Presentation on theme: "What is a Mineral pages 103-114 the building blocks of rocks Minerals of Earth’s Crust."— Presentation transcript:
1What is a Mineral pages 103-114 the building blocks of rocksMinerals of Earth’s Crust
2Mineral definitionA mineral is a natural, usually inorganic solid that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties.
3Five characteristics naturally formed inorganic crystalline structure soliddefinite chemical composition
4Naturally FormedNot man made, naturally occurring
5 InorganicOrganic means living so, this means non-living
6Crystalline structure The atoms are arranged in a pattern that repeats over and over
7SolidDefinite volume and shapeNot a liquid or gas
8Definite Chemical Composition Its chemical composition may be written down in a formula and is fairly consistent or within a range Example:Halite (salt) NaClGalena (lead) Pb
9Kinds of Minerals More than 4,000 have been identified Fewer than 20 are commonThese are called rock-forming minerals
10These ten make up 90% of the crust QuartzOrthoclasePlagioclaseMuscoviteBiotiteCalciteDolomiteHaliteGypsumFerromagnesian minerals
11Ferromagnesian mineral Contain iron and magnesium
12Two groups of minerals Silicates Non-silicates-- Based on chemical compositionSilicatesNon-silicates--
13Silicates—contain a combination of Silicon, SiOxygen, OSilicates make up more than 90% of the Earth’s crust
14Six Kinds of Silicate Mineral Arrangements Isolated-do not link with other silicon or oxygen atomsRing silicates—form rings by sharing oxygen atomsSingle-chain silicates—form by sharing oxygen atomsDouble chain silicates—form when two single chains of tetrahedra bond to each otherSheet silicates—form when each tetrahedron shares three of its oxygen with other tetrahedraFramework silicates—form when each tetrahedron is bonded to four other tetrahedra
29Hardness of some common objects 2.5 Fingernail 3 Penny 5 Pocket Knife 5.5 Window Glass 7 Steel File Learn these!
30Cleavage 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.
31Fracture A break that is not along a cleavage plane Common type is conchoidal fracture.Ex. Quartz Broken glass appearanceOr can be splinters and fibers--asbestos
32LusterThe way light reflects from the surface I. Metallic II. NonmetallicGreasySilkyPearlyGlassy
33ColorColor 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.
34Streak The color of the powdered mineral Much more reliable. Drag the mineral across a streak plate.Hematite--reddish brown to black,but usually reddish brownLimonite--yellowish brown
35Specific Gravity d=m/v Density = mass/volume A mineral’s density Densities are compared to an equal volume of waterThere is no unitQuartz SilverGold