Soil is considered to be a complex m ass containing five major components. They are: 1. mineral matter obtained by the distintergration and decomposition of rocks; 2. organic matter, obtained by Mineralogy. A mineral, as already defined, is a naturally occurring inorganic solid substance that is characterized with a definite chemical composition and very often with a definite atomic structure. In nature more than three thousand minerals are known to occur and most of them have already been thoroughly studied. The minerals generally occur in the form of natural aggregates, called rocks Epidote minerals are known since the 18 th century, but at that time the greenish to dark colored varieties were termed actinolite or schorl and not distinguished from the minerals to which these names apply today. Haüy defined the mineral species and introduced the name "epidote" in 1801, whereas Werner in 1805 used the term pistacite (quoted from Hintze 1897). Minerals form from molten rock and volcanic magma within the Earth's interior and crust. In these environments, changes in temperature and pressure and chemical composition influence the type of minerals which form, the size of their individual crystals, and their growth rate. Minerals grow from saturated solutions in rock cavities chemical properties of mineral dust relevant to estimating its main impacts. The paper reports on the scientific discussion which has taken place within the Third International Dust Workshop, held in Leipzig (Germany) in September 2008, and it is based on the results of the many field experiments which, in the last decade, have been dedicate to Properties of Common Minerals HARD- COMMON DISTINGUISHING LUSTER NESS COLORS CHARACTERISTICS USE(S) MINERAL NAME COMPOSITION* black streak, greasy feel very dense (7.6 g/cm3), gray-black streak *Chemical Symbols: Al = aluminum Cl = chlorine H = hydrogen Na = sodium S = sulfur 4. CHEMICAL AND PHYSICAL INFORMATION chemical composition of the glass can result in significant changes to its optical, electrical, chemical, and mechanical properties. Chemical glass (C-glass) is highly resistant to attack by chemicals such as hydrofluoric acid, concentrated phosphoric acid (when hot), and superheated water. The chemical Properties of Minerals: Tools for Identification • Hardness • Luster • Color • Streak • Cleavage • Fracture • Cleavage vs. crystal form • Miscellaneous properties Hardness • Measure of the resistance of a mineral to scratching (not breakage) •Mohs Hardness Scale(Softest = 1, Hardest = 10) 1 -Talc KNIFE, NAIL: 5 -5.5 2 - Gypsum 6 -Orthoclase 2.3 Properties of Minerals Minerals that do not show cleavage when broken are said to fracture. Fracture—the uneven breakage of a mineral Conchoidal Fracture Density 2.3 Properties of Minerals Density is a property of all matter that is the ratio of an object's mass to its volume. Density (D) = mass (m) Volume (V) 2.3 Properties of Minerals -As magma cools and hardens chemical bonds form -More than one mineral is produced from the same magma due to types of elements and cooling times . Minerals formed from magma Gabbro is a volcanic rock that contains quartz, feldspar and mica (minerals) Mineral Formation unique chemical composition ff 1. Color/Appearance - Many minerals will have a similar appearance, but will have different impurities. f 2. Luster - The way minerals reflect light from its surface. f 3. Hardness - How easily