Here is the short note on Distribution and states of mica in India.

1. MN-206
[INTRODUCTORY MINING TECHNOLOGY]
Presented By- BRAJ KISHOR SAH
ROLL NO.- 112CR0126

2. About MICA { Introduction }
 Mica is produced in huge proportion in India. In fact, India is one of the
leading suppliers of mica to the world.
 India alone accounts for a major portion of the world’s export of block mica and
mica splitting.
 Mica can withstand high temperature as it is a bad conductor of electricity.
Moreover , it can also be split up into thin films.
 These unrivalled properties of mica have actually made it indispensable for the
production of several electrical equipment.
 India produces approximate 90% of the world’s mica. It is an indispensable
component of the electrical industry.
 India accounts for 60% of mica embarking in international trade.

3. Etymology and History of Mica
 Mica gets its name from the Latin word Mica which literally means “a
crumb” and is assumed to be the influenced by the world Micare, meaning
“To shine or glitter.
 Mica is knows as Abharak or Abharak in Hindi. Mica has to be used in
India since ancient times.
 Finely powdered Mica have been utilised for various applications, like for
decoration.
 During the Indian festival of Holi, coloured Gulal or Abeer used by Hindus
in various parts of the country consists of fine minute crystals of mica.
 The majestic Padmanabhapuram Palace, 65 km from Trivandrum in India,
has coloured mica windows.

4. Rock with mica and Mica Ore
Rock Mica
Mica Ore

5. Mica Sheet and Mica Powder
Mica Sheet
Mica Powder

6. Padmanabhapuram Palace
The majestic
Padmanabhapuram
Palace, 65 km from
Trivandrum in India, has
coloured mica windows.

7. Mode of occurrence
 Mica-minerals occur in igneous, sedinientary and metamorphic rocks formed
under different geological conditions.
 While muscovite occurs in pegmatites of acidic nature, phologopite mica is
restricted to basic-pegmatite.
 Lepidolite occurs in pegmatites associated with topaz. Commercial biotite is
found to occur mostly in biotite-schists.

8. Types of Mica
 There are two types of Mica available in the world :-
(1) Dioctahedral
(2) TrioctahedraI
 In Trioctahedral mica, the most common types found are: Muscovite (H2KAl3(SiO4)3,
 Zinnwaldite (Li2K2Fe2Al4Si7O24),
 Biotite (H2K)(Mg,Fe)3Al(SiO4)3,
 Lepidolite (H,K)2(Fe, Al)4(SiO4)5, and
 Phologopite H2KMg3Al(SiO4)3.
 Where as Clintonite is Brittle mica.

9. Availability of Mica in World and India
World Resources
 India is the leading producer of muscovite mica followed by Brazil.
 Other producing countries are the USA, Tanzania, Rhodesia and
Argentina.
 The USA generally produces scrap mica.
 The leading producers of phologopite mica are Malagasy Republic and
Tanzania whose average annual production are 1,000 tonnes and 300
tonnes respectively.
 Small production of phologopite is reported from Canada, Tanzania and
India.

10. Brazil
 Mica is found in a number of districts parallel to the Atlantic coast.
 It is found in a belt 480 km long, 192 km wide.
 Most of the production comes from Minas Gerais State.
 Minor occurrences are reported from Bahia, Goyaz, Sao Paulo, Matto
Grosso, Ceara, Parahyba and Estado de Rio.

11. USA
 Mica production in this country chiefly comes from Spruce Pine, Franklin-
Sylva and Shelby Hickory districts of North Carolina.
 Production is mostly that of scrap mica.
 It is obtained during the mining of felspar and quartz.
 For blocks, splittings and condenser films, the USA depends solely upon
India and Brazil.

12. USSR
 Though Russia was the first country which reported production of mica,
it depends considerably on the imports from India.
 Ruby mica is mined at Telinskoye in the Chupa district of Karelia
Peninsula.
 Green mica is mined near Kyshtym, north-west of Chelyabinsk in the Urals.
 Mica-pegmatite veins in crystalline schists have been located in Mama,
Vitim, Chaya and Chara river areas in Siberia.
 Phlogopite is mined near Trkutsk, south-western end of Lake Baikal.

13. Malagasy
 Phlogopite occurs north-west of Fort Dauphin in numerous pegmatite veins
and occasionally in pockets, irregularly distributed in an oblique or normal
manner in beds of pyroxenites which are usually interstratified in the
crystalline schists of the Ampandrandava and Tranomaro groups of the
Androyan system.
 The pyroxenite beds usually range in thickness up to 50 metres and
exceptionally upto 150 metres.
 The mica veins are extremely irregular but generally range upto 1-5 metres
thick.

14.  Indian Resources
 Mica is widely available and distributed in sedimentary, metamorphic
and igneous regimes.
 Large size mica crystals, utilized for various purposes, are usually mined
from granitic pegmatites.
 In India, Mica is widely available in Karnataka, Bihar, Kolkata,
Rajasthan, Gudur and Andhra Pradesh.
 Hazaribagh, Gaya, and Munger districtsof Bihar account for a huge
proportion of the total production.
 These districts lie on the northern fringe of Chota Nagpur Plateau.

15. Indian Resources
 The remaining half is evenly divided between Nellore district in




Andhra Pradesh and Bhilwara district in Rajasthan.
Mica is also mined in small quantities in Udaipur, Sikar, Tonk and
Ajmer districts of Rajasthan.
Moreover , a small portion is also mined in small quantity in Nilgiri
district. Production has been worsening due to artificial replacement.
In India, mica belt is located along the northern fringe of the Bihar
Plateau as includes parts of Hazaribagh and Gaya districts.
Mica belt generally occurs in the veins of the metamorphic rocks.

16.  The mica belt in this region runs in the east-west direction.
 Giridih, Domchanch and Kodarma are the principle collecting centers
where it is processed.
 This particular mica belt produces more than half of the total mica
production of the country.

17. Properties of Mica
 Muscovite and Phlogopite are the most commercially significant micas that
have several uses.
 Mica’s value is based on several of its unique physical properties.
 The crystalline structure of mica forms layers which can be split into thin
sheets.
 The sheets are usually chemically inert, elastic, dielectric, flexible,
hydrophilic , platy, lightweight, reflective, resilient, refractive, and range in
opacity from transparent to opaque.
 Due to the unique combination of physical, chemical and thermal
properties, low power loss factor, dielectric constant and dielectric strength,
Mica is precious in the electric industry.

18. Properties of Mica
 The properties make mica ideal for use in condensers, the basic function of
which is to store electrostatic energy in the dielectric field like low power
loss factor and dielectric constant d momentarily perhaps one-Millionth part
of a second and then to re-deliver the minimum possible loss.
 The quality of Mica for commercial use depends largely on the amount of
staining, air inclusions, the degree of flatness and the colour.
 No other natural substance has been found to possess the properties equal to
those of mica.
 Muscovite mica can be split into flexible and transparent films as thin as
0.00025 inch, which gives added advantage in making built-up mica, tapes
and films that can be used in any shape and size and punched films that can
be used in any shape and size and punched instruments and appliances

19. Silver Mica Capacitors

20. Uses and Applications of Mica
 Sheet mica is utilised in numerous electrical and electronic appliances in
different shapes and sizes.
 Mica is used in equipments like condensers, sheostats, transformers,
electronic tubes and radar circuits as an insulating material.
 Mica is also used in form of washers, discs, tubes and plates.
 Nowadays mica is finding increasing use in equipment that encounters very
high temperatures like rockets, missiles and jet engine ignition system.
Phlogopite is used in spark plugs.
 Mica films are used in alternate layers of binding materials like shellac, alkyl
or silicon resin and then pressed and baked.

21.  In the electronic field, natural mica is mainly used in the manufacture of
capacitors such as bridge-spacers in electronic valves and as panel-board
where heat-resistance and low-loss properties at high frequencies are
required.
 The scrap mica obtained during the processing of crude mica, is utilized in
the manufacture of mica bricks for heat insulation.
 Mica powder for use as filler in rubber goods, plant, lubricant and to some
extent in plastic industries.
 It is also used in the manufacture of roofing material, welding rod, wallpaper, lamp chimneys, shades etc
 Small quantity of this mineral resource of the country is also used for the
production
of
mica
powder
and
mica
bricks.

22.  Mica powder is used in the production of rubber goods and paints.
 Mica bricks are used as an insulating material in steel and thermal and
petroleum refineries.
 Interestingly, the production of mica depends on foreign demand to a great
extent.
 Huge amount of Mica in India is exported. Countries like United States,
Japan and United Kingdom are the major buyers of mica.

23. Methods of Grinding
 Scrap mica is ground by three processes, namely:a) Dry Grinding
b) Wet Grinding
c) Micronising
The marketed product is classified according to the grinding process
which indicates quality and properties like colour, mesh size and bulk density.
 Dry mica powder is prepared by grinding in high speed hammer mills. The
edges of the flakes get crushed and powdered mica is produced which gives
the appearance of flour.
 Wet-ground mica is produced by grinding in water
involving
preferential delamination of flakes.
Churn mills, with large wheels or
rollers rotating on horizontal shafts are used for this purpose.

24. References
a.
http://www.mineralszone.com/minerals/mica.html
b. http://www.indianetzone.com/24/mica_indian_mineral resources.htm
c.
http://en.wikipedia.org/wiki/Mica
Submitted by :NAME:- BRAJ KISHOR SAH
ROLL NO.:- 112CR0126
2rd Year Student
NIT Rourkela

25. Thank You