Difference Between a Rock and a Mineral  Rock  A rock is a consolidated mixture of one or more minerals Ex Granite and Basalt  In some cases a pure mineral may also be classified as a rock  Mineral  A mineral must satisfy the following conditions; 1) Occur in nature 4) Definite chemical composition 2) Inorganic 5) Definite molecular structure 3) Solid Minerals What is a Mineral?  A naturally occurring inorganic solid with a definite chemical composition and molecular structure  Minerals can consist of elements or compounds Majority are compounds Example Galena (PbS) and Pyrite (FeS2)  Native Minerals consist of only one type of element Examples include Gold, Silver, Sulfur, Diamond, Copper Calcite Pyrite Rock Forming Minerals  The rock cycle suggest that ALL rock types originally started as igneous rock (solidified magma)  Igneous rocks form from Eight minerals called the rock forming minerals 1) Olivine 5) Plagioclase Feldspar 2) Pyroxene 6) Orthoclase Feldspar 3) Amphibole 7) Muscovite Mica 4) Biotite Mica 8) Quartz Rocks What is a Rock?  An Aggregate of minerals  Rocks are generally composed of more than one mineral For example, Granite consist of; Quartz, Feldspar, Hornblende and Mica Quartz Orthoclase Feldspar Amphibole Rocks Some common rocks include; Igneous: Granite, Rhyolite, Basalt, Gabbro, Andesite, Diorite, obsidian, Pumice, etc Sedimentary: Conglomerate, Sandstone, Shale, Limestone, etc Metamorphic: Marble, Slate, Gneiss, Schist, Phyllite, etc Sample Problem Citing two differences, distinguish between a rock and a mineral Answer: Chemical elements are the building blocks of minerals whereas minerals are the building blocks of rocks Minerals are pure solids, where all the molecules have the same definite chemical composition and structure,whereas rocks are a mixtures of minerals often appearing multi-colored