In the nineteenth and early twentieth centuries electrical apparatus relied on wood, cotton sleeving, natural waxes and. We use wave theory to explain the optical behavior of crystals. This fascinating scarce text comprises a wonderfully detailed handbook on the subject of mineralogy. Learn mineral properties with free interactive flashcards.
Correlation of crystal systems and optical classes. A variety of properties exhibited by each phase can be studied using the microscope without any modification of the instrumentor ancillary apparatus. Luster is appearance or quality of light reflected from the surface of the mineral. Why do minerals that have a hardness measurement greater than seven not have a. Pdf automated mineral identification by optical microscopy. Some of these are useful, some intriguiging, and some just fun. Animated pdfs showing optical properties of minerals john brady.
Left search window on the dvd mineral database allows users to search for minerals by their physical and optical properties and right list of minerals. The general relationship between crystal structure and optical properties is summarized in table 3. For example quartz can be clear, white, black, pink, blue, or purple. The study of physical properties of minerals will enable you to make intelligent deductions about its crystal structure and chemical composition. Study of how light passes through thin sections rock cut and polished to about 0. If a table of optical properties of minerals reports the 2v angle, it usually refers to this acute angle.
Optical properties ofartificial minerals mccrone research institute. Criddle aj, stanley cj eds 1986 the quantitative data file for ore minerals. For your information, physical properties of a mineral may be of great technological significance because a mineral may have important industrial uses that depend on its physical properties. For example, when a transparent piece of calcite is placed over printed text, the letters appear twice. Electrical and optical properties as polymer materials have developed, their excellent and sometimes outstanding dielectric properties have guaranteed their widespread use as insulants in electrical and electronic engineering. The determination of the optical properties of minerals under the microscope became one of the most important mineral identification methods in the earth sciences. This includes data on physical properties, chemical composition, crystal class and habit, optical properties, crystal structure and geological occurrence, as well as fullcolour pictures of hand specimens and photomi. This webpage provides a compilation of online instructional resources and teaching activities related to optical mineralogy and petrography. Minerals are the constituents which remain as ash after the incineration of plant and animal tissues. You might also notice how the mineral reflects light, which determines how shiny or dull it is.
Discrepancies appeared among the results obtained by various experimenters and it was soon determined that these were the result of differences in the methods used to prepare the samples. Optical properties of minerals streak optical properties of minerals streak mineralogists use the term crystal shape or habit to refer to the common or characteristic shape of a crystal or aggregate of crystals. Animated pdfs showing optical properties of minerals john brady, smith college. Assume that visible light travels in straight lines with a transverse motion vibrates at right angles to direction of propagation. Grim illinoisstategeologicalsurvey,urbana,illinois abstract analysesofmanyclaysbyxray,optical,chemicalanddehydrationmethods ha. Use properties of light absorption and propogation through a mineral a affected by atomic arrangement and composition. The first two steps, sawing and preforming, are the most important because they dictate the shape and influence the final weight.
Most people assume that stones are dull, grey objects, and that you need something organic or manmade to be brightly coloured. Origin of elements and compositionstructure of the earth, physical properties of minerals, chemical properties of minerals, chemistry and structure of minerals, optical properties of minerals, isotropic and uniaxial minerals, biaxial. The most important of these properties are listed below colour transparency lustre reflection and refraction streak fluorescence colour the colour of minerals is the result of the selective absorption of white light. Optical mineralogy and petrography serc carleton college. Other minerals, such as tourmaline, also exhibit a variety of hues, with multiple colors sometimes occurring in the same sample. Hardness mohs hardness scale color streak luster density crystal systems cleavage and fracture special properties flourescence double. Snells law acrobat pdf 156kb feb11 09, vector resolution acrobat pdf 444kb feb11 09, retardation acrobat pdf 3. However, many minerals occur in more than one color, so you would need to examine other properties as well. This procedure is critical to the faceting process. The relative reflectance data were transmitted to storage files on the university. Optical properties are important because they provide a nondestructive means for identifying gemstones and are responsible for all the features one immediately observes and admires including color, luster, brilliance, scintillation, and dispersion, as well as special phenomena, play of colors, labradorescence, and the like.
This optical property is known as double refraction other properties of minerals. This is an ideal textbook for both advanced undergraduates and graduate students. These properties are extremely useful for identifying a mineral. Optical properties of common minerals name crystal system indicatrix optical sign birefringence color in plain polar anorthite. Optical properties chapter 9 minerals cambridge university press.
The study of minerals using optical techniques, principally employing a petrographie microscope, is most commonly undertaken to obtain information such as mineral identity, chemical composition and structural state, and growth and strain history. This shows a light beam incident on an optical medium. In this section you will read about how the properties of a mineralincluding its. This chapter gives the physical, mechanical thermal, and optical properties of. The minerals represent those covered in optical mineralogy ersc 2p22 with the remainder being introduced in igneous and metamorphic petrology ersc 3p21. Optical properties of natural minerals and other materials. Electromagnetic spectrum of radiation spans the wide.
Optical properties glasses are among the few solids that transmit visible light thin film oxides might, but scattering from grains limit their thickness mica windows at acoma pueblo glasses form the basic elements of virtually all optical systems. The chemical structure of each mineral allows only certain. Free mineralogy books download ebooks online textbooks. Optical properties are important because they provide a nondestructive means for identifying gemstones and are responsible for all the features one immediately observes and admires including color, luster, brilliance, scintillation, and dispersion, as well as special phenomena, play. White light, or visible light, is a form of electromagnetic radiation energy waves produced by the motion of an electric charge. Focusing on the different ways minerals can look, this quiz and corresponding worksheet will help you gauge your knowledge of the optical properties. However, in contrastwith the study of thinsections in transmittedlight, these properties. Introduction to optical mineralogy by william d nesse. Hardness mohs hardness scale color streak luster density crystal systems cleavage and fracture special properties flourescence.
A study of these rockforming minerals entails their examination under the microscope, either as tiny grains or as thin 0. Choose from 500 different sets of mineral properties flashcards on quizlet. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. In more complicated situations, numerical solutions are necessary. Learn the properties of light associated with techniques governing the use of a petrographic microscope. Optical properties minerals have many interesting optical properties. Automated mineral identification algorithm using optical properties.
But as we shall see other factors also come into the picture when dealing with optical properties optical operating in or employing in the visible part of the electromagnetic spectrum or relating to sight, especially in. But as we shall see other factors also come into the picture when dealing with optical properties optical operating in or employing in the visible part of the electromagnetic spectrum or relating to sight. Pseudocubic or dipyramidal to tapering, needlelike. In biaxial minerals we call the plane that contains x and z, and the 2 optic axis the optic plane. A few minerals exhibit somewhat regular polygons that are helpful in their identification. Introduction to optical mineralogy by william d nesse alibris. A comparison of the optical properties of a mineral material j in crystalline and.
Identifying minerals each mineral has its own specific properties that can be used to identify it, this is due to the fact that each mineral has its own unique makeup. Also, a dark piece of glass may appear to be opaque if it is thick enough. Optical properties of materials optical reflectance and absorption introduction to optical reflectance and optical absorption board teaching and ppt light interaction with materials. Optical properties many of the optical properties are closely related to the electrical properties of the material. Several important optical properties are applicable to minerals and gemstones, and can be very useful for gem identification. It contains valuable coverage of the optical properties of minerals, as well as uptodate descriptions of common rockforming minerals. Optical properties of common minerals select one of the minerals listed below to get a summary of the optical data and view representative plane light and crossed polar images. Remember that glass can be almost any color, including black, so dont be fooled by the color. Optical properties of metals 343 interested in measuring either the reflectiity66the absorption or coefficient and have not determined the optical constants. Optical property of a material is defined as its interaction with electromagnetic radiation in the visible. Thus, the use of color as a means of identification is often ambiguous or even misleading. With proper equipment, jewelers can easily distinguish a ruby from garnet or red glass, even if their outward appearance may be identical. Nesse online download introduction to optical mineralogy ebook free type. The optical properties of minerals are characteristic and serve for mineral identification.
Other applications of crystalline optical materials make use of their directional properties, particularly those of noncubic i. The wideranging optical properties observed in solid state materials can be classified into a small number of general phenomena. The study of minerals using optical techniques, principally employing a petrographie microscope, is most commonly undertaken to obtain information. In more complicated situations, numerical solutions are nec. Nature of light em radiation to account for all properties of light we need wave theory and corpuscular theory.
As enantimorphic prismatic crystals, with f1010g terminated by f1011g and f0111g, striated. Hauser j, wenk nr 1976 optical properties of composite crystals. Mineral properties revised on 8272012 page 3 of vitreous lusteris like that of glass, shiny and translucent to transparent. Minerals can be identified based on physical properties. The chapters on optical theory include discussions of the nature and properties of light, the petrographic microscope, and the. The most obvious visual property of a mineral is colour. Optical properties of dielectric and semiconductor thin films 3 analytic solutions can be given if we assume that the incident wave is a pure wave and that the boundary layers are regular. Relief is a useful distinguishing property for the the igneous rockfroming minerals. This chapter deals with the optical properties of those minerals which make up the common rocks of the earths crust, the socalled rockforming minerals. Introduction to optical mineralogy book by william d. However, even in the case where analytic calculations.
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