FULLER'S EARTH RESOURCES OF RAJASTHAN
Fuller's earth is a name given to a particular type of clay which consists of many
clay minerals.
mntmorillonite group containing a varying amount of which is also attapulgit
supposed to be a hydrated alumino-silicate without any definite structure.
Fuller's earth very much resembles to bentonite, in fact calcium bentonite. Is
usually reffered to as fuller's earth and sodium bentonite as bentonite only. It is
characterised by lack of plasticity, large water content, fo.Hated structure and
tendency, when water is removed from the clay, to adhere strongly to the
tongue. It has a variable colour which varies from cream to yellow, yellowish
brown, buff, pale greenish grey and light grey. When freshly excavated, it is
quite soft but hardens considerably on exposure. It has a remarkable high
absorbing power for basic colours and removes these colours from solution in
animal, vegetable and mineral oils as well as from other liquids including water.
It is tasteless and disintegrates in contact with water but unlike bentonite or
montmorillonite
does not swell and usually as plastic as other clays or
clay minerals. It has a lower specific gravity which varies from 1.75 to 2.5.
Chemical analyses of different samples of fuller's earth differ so much from one
another that they don not afford a criterion in the classification of any clay as
fuller's earth or not. The only reliable test for fuller's earth is its decolourising
property.
The difference between bentointe and fuller's earth lies in their mode of
occurrence and other physical properties. Bentonite is regarded to have been
formed by the alteration of of volconic ash deposits, mostly under Cretaceous
formations. Fuller's earths represent a shaly facie of Tertiary rock.
Bentonite swells when added to water and form a gel; Fuller's earth is non
swelling but possesses inherent bleaching and absorbing ability.
Recoverable reserves of fuller's earth (as on 1.4.1995) are placed at 228.3
million tonnes out of this, almost the entire reserves (99.7 %) are placed under
possible category and about 83% reserves are located in the Banner, Bikaner
and Jaisalmer districts of Rajasthan and the rest in other states.
Total production of fuller's earth came from the two states: Rajasthan and
Karnataka. Rajasthan accounted for the major share of 86.6% and the remaining
13.4% was the contribution of Karnataka.
Occurrence in Rajasthan
Rajasthan possesses good deposits of fuller's earth. The main production of
fuller's earth is from Barmer district, which contributes 77% while the districts
of Bikaner and Jaisalmer contribute 18% and 5%, respectively.
Barmer district
Kapurdi: Kapurdi village is situated on National Highway No. 15 lying
between Barmer and Jaisalmer at about 28 kms. north of Barmer town. In
Kapurdi area fuller's earth occurs in a shallow basin roughly 1.5 km. long and
250 m. wide with an approximate north-south axis. The maximum thickness (50
m.) of the fuller's earth is found near the centre of the basin and the beds thin
out towards the southen and northern boundaries of thti basin. The fuller's earth
is well bedded, nonarenacens, creamy yellow or yellowish brown in colour and
occurs at 2 to 5 m. below surface. Imperfectly preserved cast of some molluscs
and echinoids are found in the fuller's earth and in the ironstone bands occurring
intercalated in it. .
Based on exploratory borehole data, collected during investingation for lignite,
the inferred reserves of fuller's earth in an area of 6.37 sq. km. are of the order
of 78 million tonnes assuming specific gravity 2.00.
Acid activation tests of fuller's earth from this area conducted at R.R.L.,
Hydrabad have indicated that fuller's earth could be-activated acid treatment and
the product obtained was comparable to imported bleaching earths. Similar tests
on the fuller's earth samples have been conducted by departmental ceramic
laboratory and the results show that the sample having above 1.0%
exchangeable calcium oxide has given best results when activated with 25%
sulphur acid followed by thermal activation at 350°C.
Bharka: Bharka is located about 22 km. from Barmer district on National
Highway 15 connecting Barmer and Jaisalmer districts. At Bharka village, a 3
m. thick fuller's earth occurs bed is found to occur at about 15 m. depths.
Rohli: Another deposit of fuller's earth occurs at a distance of 1.5 km. east of
Rohli village. The material appears to be of good quality and it can be excavated
in large lumps.
Alamseria-kurla: The deposit is situated about 6 km. distance from Barmer on
Barmer-Balotra road. The fuller's earth bed in the area is. over 8 m. in thickness
and is overlain by a 2-3 m. thick sub Recent calcareous conglomerate with
pebbles and boulders of volcanic rocks. The deposit is fairly large covering
about 1 sq. km. area.
Sheo: Fuller's earth is exposed for about 120 m. in nala cutting, about seyen
furlongs east of Sheo, where the land is mostly covered by some calcareous
material and pebbles of quartz. Here fuller's earth is light yellowish in colour
flaky and in appearance resembles the fuller's earth from Kapurdi area. The bed
of fuller's earth in this area is more or less horizontal; as such it can be safely be
taken to extend for about 80 m. on each side of the nala. The tentative reserve
available in this area is of the order of 100,000 tonnes.
The occurrence of fuller's earth is also observed near Joranda, Lalu Kothri,
Jilala and Hemnada.
Bikaner district
Fuller's earth deposits of Palana are situated about 23 km. SW of Bikaner city.
In this area the fuller's earth occurs in the Palana shals over laying the lignite
seam. It has a thickness of 1.8 to 2.4 m. and occurs at about 50 m. depths from
the ground level. It stretches over the entire Palana coal field and is roughly 5
km. in length and about 750 m. in width. It is silvery white, translucent,
possesses good lusture, siliceous in parts and slightly colored yellowish. In past
it was mined through a number of shafts sunk exclusively for this. These were.
known as the "Multani Mitti Shafts" and had yielded some production for a few
years but later due to the difference in quality and also high cost of production,
those were closed. The estimated reserves are of theorder of 85 million tonnes.
Kolayat: Kolayat is located at 51 kms. SW of Bikaner. In this area, the in two
horizons,. namely upper and lower. Only the upper horizon formthe main
deposit and is of "economic value.
Upper Horizon: The fuller's earth of this horizon is located between Marh and
Jogira Talab, about 7 kms.North of Marh, and is exposed along the escarpment
of the cuesta. The best exposures occur at 1 km. south and 500 m. south east of
Jogira Talab where its thickness is 11 m. and 7 m., respectively. The fuller's
earth of this horizon is grey to greyish yellow and reddish, soft, well bedded
foliated with shale and shaly limestone partings. The thickness of the recent
formation on the top of the cuesta is 3 to 10 m. increasing towards Jogira Talab.
The probable reserves of high grade and low grade fuller's earth are 4.33 and
2.77 MT, respectively. Besides this, the inferred reserves are 12 million tonnes.
.
Indo-Ka-Bala: The area is situated about 400 m. north of village Indo-Ka-Bala
and about 1.6 km. west of village Chandi. The fuller's earth bearing area proved
as a result of prospecting by state department extends to about 14, 00,000 sq.
feet. As a result of prospecting it appears that the average thickness of the
workable bed of fuller's earth varies .between 8 to 10 feet, with an average over
burden between 5 to 6 feet.
The total reserve of the workable quality of fuller's earth comes to 3.5 lacs
tonnes.
An occurrence of fuller's earth near Kesardesar is also. reported by Department
of Mines and Geology during exploratory drilling for lignite.
Nagaur district
In Nagaur district Kuchera-Khajwana Formation (Eocene age) is reported to
contain fuller's earth associated with ferruginous gritty felspathic sandstone,
black shale and lignite. An occurrence of fuller's earth about 10 m. thick in a
well section, 1.5 km. north of Igiar was located by G.S.I. It appears to occur as
small pocket and lenses and is generally mixed with angular quartz grains. Good
quality fuller's earth is exposed in well section of Arisar, Deswal and Chhapri.
Jaisalmer district
In Jaisalmer district fuller's earth occurs at Mandha and Khuiala, associated with
Khuiala limestone. Near Mandha it is 0.60 to 2.75 m. thickness and a reserve of
80 thousand tonnes has been estimated. Near Khimsar, Pangli, Khuiala and
Bandah, it occurs as 0.5 m. to 1.5 m. thick band associated with Eocene
limestone. Near Dhalo-Ki-Dungri, a 3 m. thick fuller's earth bed is reported to
occur. Minor occurrences are reported in sam and Ramgarh areas.
Uses
Fuller's earth was originally used as fulling or cleaning the grease and stains
from wool and cloth. It is used for bleaching (decolourizing) cotton, wool and
oil. Usually it is used to clean lard oil but is also used for castor, linseed,
coconut and other oils as well as tallow and greases. Mineral oils are also
cleaned by fuller's earth. It has also been used as a carrier for colours in cheap
pigments used in wall paper printing. It possesses good absorbing ability and
requirements for this purpose are : (a) it must bleach well (b) it must not cause
the oil to revert to its original colour (c) it must be of open texture pocket and
lenses a quartz grains. Good quality fuller's earth is nd is generally so that it
must filter well (d) It must not absorb more oil. (e) It must not catch fire when
removed from thefilterpress. (f) It must not give any permanent taste or colour
to the oil.
Extended use of fuller's earth is in refining and bleaching of glyceride oils;
clarification and purification of sugar cane juce, syrup and wines; water
purification; sewerage and effluent treatment absorbent for oil spillage and
factory floors, pet and' animal litter; as a carrier for insecticides and fungicides :
and as mineral filler and extender.
Specification
The specification for fuller's earth depends hugely on the nature of the work to
be done. For refining vegetable, animal and mineral oils by the contacting
method, finely pulverized clay is used, having a mesh of at least 50 pct through
200 and generally from 85 to 95 pct through 200. The limiting factors on finess
are filter rate, or the speed with which the oil can be separated from the clay
cake after contacting and oil retention. When the percolation method is used, a
coarse mesh is required in order to permit free passage of the oil through the
clay. The most popular percolation grade is that known as 30/60 mesh. Other
standard-mesh percolation grades are 60/90 and 15/30.
District wise No. of Leases, Production
Sale- Value and Revenue of Fuller's Earth in Rajasthan (Year 2000-2001)
District
No. of leases
Production
Sale value
(000'T)
(Lacs Rs.)
Revenue
(000'Rs)
Barmer
15
13.140
13.74
1
0.000
0.000
5
1.808
0.27
1
0.259
0.05
22
15.807
14.06
365.29
Bikaner
50.00
Bundi
18.08
Bhilwara
5.91
Total
439.28
Statistical Information of Fuller's Earth in Rajasthan (Year 1997-2002)
Year
Production
Revenue
No.
(000'T)
(000'Rs.)
1997-1998
21.940
1003.89
26
1998-1999
17.843
1090.13
23
1999-2000
15.230
762.07
24
2000-2001
17.000
389.15
19
2001-2002
15.807
439.28
22
of Leases