UNIT II MINEROLOGY Physical properties of minerals – Quartz group, Feldspar group, Pyroxene - hypersthene and augite, Amphibole – hornblende, Mica – muscovite and biotite, Calcite, Gypsum and Clay minerals. 2.1 Physical properties of minerals Mineralogy: It is defined as naturally occurring inorganic solid substance that is characterized with a definite chemical composition and very often with a definite atomic structure. It is a branch of geology, which deals with the various aspects related to minerals such as their individual properties to their mode of formation and mode of occurrence. The physical properties of minerals are: i) Colour ii) Luster iii) Streak iv) Hardness v) Cleavage vi) Fracture vii) Tenacity viii) Structure …show more content…
The softest is assigned a value of 1 and the hardest value of 10. Hardness of any mineral will lie in between these two limits. Specific gravity: It may be defined as the density of the mineral compared to the density of water and as such represents a ratio i.e specific gravity of a mineral is the ratio of its weight of an equal volume of water. Specific gravity of a mineral depends upon the weight and spacing of its atoms. Cleavage: It is defined as the tendency of a crystallized mineral to break along certain definite planes yielding more or less smooth surfaces. Cleavage is related to the internal structure of a mineral. The cleavage planes area always parallel to some faces of the crystal form typical of mineral. It is also described on the basis of perfection or the degree of easiness with which minerals can split along the cleavage planes. Fracture: The fractures of a mineral may be defined as the appearance of its broken surface. Common types of fractures are: (i)Conchodal fracture - The broken surfaces shows concentric rings or curved surface. (ii)Even fracture - When the broken surface is smooth and
More recently than Zeck’s work, Cesare et al. (1997), only divided the xenoliths into two main types: garnet-biotite-sillimanite and spinel-cordierite xenoliths. The quartz-cordierite rocks, distinguished by Zeck (1970), were interpreted as the products of interaction between garnet-biotite-sillimanite xenoliths and blebs of mafic magma and are not recognised. The xenoliths were observed to contain widespread occurrences of rhyolitic glass as...
A bauxite is a mixture consisting of hydrated aluminum oxide minerals and mineral impurities which are formed by weathered aluminum bearing rocks. In 1891 bauxite was mined in Alabama from the Rock Run. However, mining came to a sudden stop because metallurgical grade bauxite became very hard to obtain. Production started back up in 1927 and has been running on a maintained basis. Due to irregular distributions of bauxite deposits, exploratory test drilling must be conducted before any mining. Alabama bauxite is used in the making of high temperature products, abrasives, and chemicals. (Tew, 6)
Aluminum is the most abundant metallic constituent in the crust of the earth; only the nonmetals oxygen and silicon are more abundant. Aluminum is never found as a free metal; commonly as aluminum silicate or as a silicate of aluminum mixed with other metals such as sodium, potassium, iron, calcium, and magnesium. These silicates are not useful ores, for it is chemically difficult, and therefore an expensive process, to extract aluminum from them. bauxite an impure h...
Fractures occur when a force is placed on a bone and the force is greater than the bone can withstand. A greenstick fracture is most often caused by:
Due to the natural processes of magma flow, hydrothermal gradients, sedimentation, and evaporation, minerals are concentrated in various areas of the Earth’s crust. Obtaining these minerals for human use involves four general steps. • Locating the minerals • Then, extracting the minerals from the Earth in the form of ore or rock Then, processing (smelting) the ore to separate the impurities from the desired mineral. Finally, creating a useful product from the minerals. Procedure 1.
Complete means when a fracture is completely though the bone. A communited fracture is when the broken bone has shattered into numerous smaller pieces. Intertrochanteric is when a fracture is located between the greater trochanter and lesser trochanter of the femur.
The organic substance is composed of carbon and commonly in combination with hydrogen, oxygen, nitrogen, chlorine, phosphorus, or other elements (Sanferstein, 2011, Pg 123). Inorganic substances are a compound not based on carbon or it can encompass other known chemicals. In order to classify both compounds they must be classified according to what physical form it takes. Saferstein lists the three forms that fall under: solid, liquid, and gas. “A solid is rigid and therefore has a definite shape and volume. A liquid also occupies a specific volume, but its fluidity causes it to take the shape of the container in which it is residing. A gas has neither a definite shape nor volume, and it will completely fill any container into which it is place” (2011, Pg. 120). Chromatography, spectrophotometry, and mass spectrometry are used to identify or compare organic materials. As explained by Saferstein “Chromatography is a means of separating and tentatively identifying the components of a mixtur...
The micro hardness of the prepared samples were obtained by using a Vickers Micro hardness Tester (Model : Leco LV 700, USA). 5 readings were taken for each sample to calculate the average hardness. An indentation load of 5gf was used. After calculating the average hardness for each sample, mean variance and standard deviation (S.D.) was calculated to check the consistency of the data.
Stable fracture. This includes a single fracture line through one bone, with no injury to ankle ligaments. A fracture of the talus that does not have any movement of the bone on either side of the fracture line (displacement)
One very important piece of information is that gemstones and crystals are grown during the cooling, formative stages of Earth’s development and so it has lead me to the conclusion that they are gifts from nature. According to physics, gemstones and crystals consist of natural balances and solid sta...
Crystalline silica may be of several distinct types. Quartz, a form of silica and the most common mineral in the earth's crust, is associated with many types of rock. Other types of silica include cristobalite and tridymite.
Chemical Weathering is when water weakens the structure of the rock and Mechanical Weathering is where water seeps into the rock face causing fragments of rock to break off.
When people think of geology, they usually think of rocks and fossils. However, geology is actually a very large field of study. The knowledge of geologists ranges from rocks and fossils to the moon and other planets (Hammonds 7-8). Geologists use a variety of subjects in their work, but the sciences and math are the most important. Some of the sciences geologists study are physics and chemistry (12). English is also a subject that geologists use when communicating with other scientists, the media, and the public (12) . Because of these tasks, it is important for geologists to have a wide knowledge of these different subjects.
Igneous rocks are formed from the ejection of earth’s volcanoes. Deep down inside earth’s mantle there lies hot magma. Magma is molten rock that is kept below the surface. This mixture is usually made up of four parts: a hot liquid substance which is called the melt; minerals that have been crystallized by the melt; solid rocks that have made themselves tangled in the melt because of loose materials, and finally gases that have become liquid. Magma is created by an increase in temperatures, pressure change, and a alter in composition. When this magma is ejected from earth’s crust it earns a new name called lava. The lava hardens and becomes an Igneous rock.
Toughness is the ability of a metal to mutilate plastically and to absorb energy in the process before it breaks or fracture. Metals can be heat treated to alter the properties of strength, ductility, toughness, hardness or resistance to corrosion. This can be done by using heat treatment processes which include precipitation strengthening, quenching, annealing and tempering. Annealing and tempering are the most prominent methods for treating metals. A material may become more or less brittle, harder or softer, or stronger or weaker, depending on the treatment used.