Muscovite mica

Muscovite Mica in details...

1. MUSCOVITE MICA By- Ashish Ranjan , 12411008

2. What is Mica? Mica is a generic term applied to a group of rock-forming complex aluminosilicate minerals having a sheet or plate like structure with varying chemical composition and physical properties.

3. Types Of Mica Of the nine common varieties in the mica group of minerals, the two principal classes of Mica types of commercial importance are  Muscovite :   K Al 2  (Al Si 3  O 10  )(OH)  2    and   Phlogopite : K Mg 3  (Al Si 3  O 10  )(OH)  2

4. Muscovite Mica It   is a hydrous potassium aluminium silicate with a predominance of potassium. It ranges from colourless through browns to greens or reds.

5. Phlogopite Mica It   is a hydrous magnesium aluminium silicate with a predominance of magnesium. It is commonly called as “Amber Mica” which varies in colour from light silver to dark brown or amber.

6. Occurence Muscovite is the most common mica, found in Granites, Pegmatites , Gneisses , and Schists , and as a contact metamorphic rock or as a secondary mineral resulting from the alteration of Topaz , Feldspar , Kyanite , etc. In Pegmatites , it is often found in immense sheets that are commercially valuable.

7. Exploration and exploitation is successfully carried by means of systematic vertical shaft and open cast mining . The principal muscovite mica deposits are chiefly found in the States of Jharkhand, Rajasthan and Andhra Pradesh . Jharkhand (formerly Bihar State) which produces the world's finest muscovite mica well known throughout the globe

8. Muscovite Mica  may be divided into two color groups : Ruby Muscovite Green Muscovite  

9. Ruby Muscovite  Colour ranges from an almost white through pink to a light ruby and into shades of brownish ruby and brown . It is produced in the Indian States of Jharkhand and Rajasthan .

10. Green Muscovite  Ranges from light to pale green through yellowish and olive green to a dark green. It is produced in the Indian State of Andhra Pradesh. 

11. Physical Properties Lustre -Vitreous, Silky, Pearly Diaphaneity (Transparency): Transparent, Translucent

12. Colour: White to colorless, silvery-white, and tinged various colors by impurities. Streak: White Hardness ( Mohs ): 2½

13. Cleavage: Perfect Perfect on {001}. Fracture: Micaceous Crystal System: Monoclinic with a = 5.199Å, b = 9.027Å, c = 20.106Å β = 95.78°

14. DISTINGUISHING SIMILAR MINERALS Chlorite  and  Margarite   - Not as  elastic  as Muscovite . Biotite ,  Phlogopite  - Usually darker in color, otherwise very difficult to distinguish . Lepidolite  - Very difficult to distinguish from pink Muscovite . Gypsum  - Cannot be peeled into  micaceous  sheets, crystals usually differently shaped.

15. Uses

16. THANK YOU

17. Muscovite is an extremely common mineral, some bright yellow and others with perfect star formations, come from the famous  pegmatite localites in the Doce and Jequitinhonha Valleys in Minas Gerais Brazil. Specific localities include  Divino das Laranjeiras ("stars"), Galileia , Governador Valadares, Conselheiro Pena, Jaguaracu , Aracuai , and Coronel Murta . Beautiful yellow Muscovite comes from the Davib Ost Farm, Karibib , Erongo , Namibia. Fine Muscovite plates, often associated with valuable  pegmatite gemstones , come from the Shigar Valley and Skardu District in Northern Pakistan. Nellore, India, is famous for its Muscovite mines which have produced some of the worlds largest mica sheets. Xuebaoding Mountain, Pingwu , in Sichuan Province, China, provides excellent  Aquamarine  and  Scheelite  that are associated with beautiful Muscovite plates. In the U.S., Muscovite is fairly common in the pegmatites of San Diego county, including Pala and Ramona. Rare Muscovite pseudomorph s after  Tourmaline  come from the Willow Spring Ranch, Oracle, Pinal Co., Arizona. A bright pink, lithium-rich variety comes from the Harding Mine, Taos Co., New Mexico; and  gemmy  green crystals from Lincoln Co., North Carolina. Other important localties include Mt Antero, Chaffee Co., Colorado; the Diamond Mica Mine, Keystone, Pennington Co., South Dakota; Shelby, Cleveland Co., North Carolina; and Bedford, Westchester Co., New York. New England contains some important Muscovite in its famous pegmatites, specifically at Middlesex Co., Connecticut (East Hampton, Haddam, and Portland); Grafton Co., New Hampshire (the Palermo No. 1 Mine, Groton; and the Ruggles Mine, Grafton); Mt. Apatite, Auburn, Androscoggin Co., Maine; and Greenwood and Newry , Oxford Co., Maine.