Identification of minerals

Identification of minerals is an activity to make a description of a particular mineral. Once the identification is done, then we can clearly give the name of the mineral. Minerals are inorganic materials which form naturally, has a fixed chemical composition and crystal structure of irregular yan. In nature there are more than 2000 kinds of minerals that have been known. However, only a few minerals are found as rock-forming minerals. Mineralmineral can be identified based on the nature fisisnya specifically, among others: 1. Lightning (luster) 2. Color (color) 3. Hardness (h ardness) 4. Spout (streak) 5. Hemisphere (cleavage) 6. Fractions (fracture) 7. Shape (form) 8. Density (specific gravity) 9. The nature of the 10. Magnetism 11. Electrical 12. Melting Power In this lab are only required to identify the mineral that is only visible to the naked eye and magnifying glass just assisted. As for the properties of numbers 8-12 further studies are needed in particular. 1. Lightning Lightning often called an appearance of a mineral glow indicated by the reflection of light applied to it. Quick outline is usually divided into two types: a. Lightning Metal (metallic luster): if the mineral has a flash like a metal. b. Lightning Non-Metals (non-metallic luster), divided into: • Lightning diamond (adamantin luster); brilliant as diamonds. • Lightning glass (vitreous luster); for example quartz and calcite. • Kliat silk (silky luster); generally present in minerals that have fiber, such as asbestos and gypsum. • Lightning resin / resin (resinous luster); lightning like gum resin / resin, for example mineral sphalerit • Lightning pearl (pearly luster); lightning like fat or soap, such as serpentine, opal and nepelin. • Lightning ground flash like clay, eg kaolin, bauxite, and limonite. 2. Color The color of minerals is a direct appearance that can be seen, but not reliable in the identification of minerals as a mineral can have more than one color. For example, quartz can be milky white, purple, dark brown or colorless (clear). Some examples of mineral colors: - Quartz: white, clear, milky white and has no parts. - Mica: if white is named muscovite, when black is named biotite, both characterized by the existence of sheet-like parts. - Feldspar: if red meat is named ortoklas (field perpendicular sides / 90 °), when the gray-white color called plagioclase (parts of the twin crystal). - Carbonate: This mineral is usually given the name of calcite and dolomite, the main feature of these carbonate minerals are reacted with HCl. - Olivine: green (grains / granular), usually yellow or greenish like sugar. - Pyroxene: short prismatic shaped blackish green. - Amfibol: long black shiny prismatic shaped - Iron oxides: a yellow-reddish-brown - Clay: when a white sheen of land called kaolin that is the result of weathering of feldspar, and gray when called Illit is the result of weathering muscovite. - Azurit: when blue - Jasper: when the red

3. Violence Violence is the resistance of a mineral to scratches. Violence relative of a mineral can be determined by comparing a mineral with certain minerals. The scale of violence used is a scale created by Mohs Friedrich of Germany, or better known as the Mohs scale. Mohs Scale starting from 1 to 10 scale, with a scale ranging from minerals and scale terlunak 10 is the hardest mineral. Smaller scale would have scratch marks when worn on a larger scale.
For comparison of scale mentioned above, it can be given the scale of violence to: - Fingernails: 2.5 - Copper coins: 3 - Knives / steel nails: 5.5 - Broken glass window: 5.5 to 6
4. Spout Spout is the color of minerals in the form of crushed (powder). This can be obtained if the mineral streaking a rough part of a piece of porcelain or can be done by then seen the color of powdered mineral powder. Spout can be either the original color of the mineral, may also differ. 5. Hemisphere Hemisphere is the tendency of certain minerals to divide da one or more in a particular direction. Hemisphere is one of the physical properties of minerals caused by external pressure or beating with a hammer. The meaning apart is when we are at the mineral will not be destroyed, but split through the slippery parts of the field. So it can be used also the term there is a field or without field split apart. For example: calcite has a three-way hemisphere, but quartz does not have the parts. 6. Fraction When the parts of the mineral will break in the regular direction, whereas on mineral fragments will break irregularly. The difference field split on the sides will appear in a mirror reflects the light like a flat, while the fractions would reflect light in all directions with irregular. Several types of mineral fractions are as follows: • Concoidal: when the waves show curved, like the broken bottle. • fibrous: If symptoms such as fiber fractions, for example asbestos. • Event: when the fractions showed a smooth field of fractions, such as clay minerals. • Uneven: when the fractions showed a rough area of ​​fractions, for example mineral magnetite or iron miberal. • Hackly: when the fractions showed areas of irregular fractions of rude and pointed, for example, silver or gold minerals.
7. Form Mineral anyone has a crystal structure, some that have no shape or crystalline structure. The minerals have a crystalline mineral called crystalline form, while those not having a crystal form called amorphous.