Mineral Identification Guide PDF
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Uploaded by WellRegardedZinnia
Misr University for Science and Technology
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Summary
This document provides a detailed description and microscopic examination of various minerals, including Kieselguhr, Talc, Chalk, Sulphur, and Starch. The document includes information on their origin, description, special tests, and microscopic images. It is helpful for students or researchers studying minerals.
Full Transcript
# Kieselguhr - **Origin:** Mineral consisting of siliceous skeleton of fossil diatoms - **Family:** Bacillariaceae - **Description:** - Like top and bottom of a box, the flat surface called valve and rims called girdle. - The valves have several shapes as: - Rounded discs -...
# Kieselguhr - **Origin:** Mineral consisting of siliceous skeleton of fossil diatoms - **Family:** Bacillariaceae - **Description:** - Like top and bottom of a box, the flat surface called valve and rims called girdle. - The valves have several shapes as: - Rounded discs - Oval discs - Triangular discs - Pinnate shapes - The valves show sculptures as spongy spicules and honey combed appearance. **Microscopical Examination:** - **Diagram:** - A diagram depicts a valve with the following labels: - Epivalve - Girdle - Hypovalve - Shapes of valves are illustrated as: - Rounded - Oval - Triangular - Pinnate - Additional illustrations of the following valve appearances are provided: - Honey Combed appearance - Spongy spicules # Talc - **Origin:** Purified native hydrated Mg-trisilicate and few Al<sub>2</sub>O<sub>3</sub> + FeO - **Description:** Thin plates with sharp jagged laminated edges - **Special Test:** Talc floats on water surface. - **Microscopical Examination:** - **Diagram:** A diagram depicts jagged laminated edges. # Chalk - **Origin:** - Chemical compound from chemical reaction: - CaCl<sub>2</sub> + Na<sub>2</sub>CO<sub>3</sub> - **On Cold:** CaCO<sub>3</sub> (Light Chalk) - **On Hot:** CaCO<sub>3</sub> (Heavy Chalk) - **Description:** - **Heavy Chalk:** Macrocrystals, rectangular with irregular shape. Occur single. - **Light Chalk:** Microcrystals, adhere together in groups. - **Special Test:** Powder + drops of HCl → effervescence + CO<sub>2</sub> - **Microscopical Examination:** - **Diagram:** A diagram depicting a heavy chalk and light chalk # Sulpher - **Origin**: Chemical element from chemical reaction: - Ca(OH)<sub>2</sub> + Sublimable (S) → Ca-polysulphide conc. HCl (S) p.p.t. - **Description:** Amorphous masses indefinite (irregular) in shape and size appear shiny in dark background. - **Special Test:** Yellow powder with burnet sulphur like odour. - **Microscopical Examination:** - **Diagram:** A diagram depicting undefined shape of sulphur # Starch | Microscopical Examination | Potato Starch | Wheat Starch | Maize Starch | Rice Starch | |---|---|---|---|---| | **Description:** | Oval - pyramidal | Rounded | Polygonal with rounded edges. | Polygonal with sharp edges. | | **1 - Size:** | Large | Medium | Medium but> wheat | Small | | **2 - Shape:** | Oval - pyramidal | Rounded | Polygonal with rounded edges. | Polygonal with sharp edges. | | **3 - Hilum**| - Present - Eccentric - pointed. | - Present - Centric - Pointed | - Present - Centric - Fissured or cleft | Absent | | **4 - Striation** | Concentric rings | Concentric rings but faint | Absent | Absent | | **5 - Aggregation** | Mostly simple, semi-compound. | Mostly simple | Simple and few compound | Mainly compound and few simple. | # Origin of Starches | Starch | Origin | |---|---| | Potato | It consists of the poly saccharide granules obtained from the tubers of *Solanum tuberosum*. Family Solanaceae. | | Wheat | It consists of the poly saccharide granules obtained from the endosperm of the grains of *Triticum vulgare*. Family: Graminae | | Maize | It consists of the poly saccharide granules obtained from the endosperm of the grains of *Zea mays*. Family: Graminae | | Rice | It consists of the poly saccharide granules obtained from the endosperm of the grains of *Oryza sativa*. Family: Graminae |
