Natural Colours of Terracotta & Its Commercial Use

Natural colours of

terracotta & its

commercial use

UJWALA GUJARYOGESHA PRAJAPTIRAJKUMAR PRAJAPI

Natural colours of terracotta & its commercial use

UJWALA GUJARYOGESHA PRAJAPTIRAJKUMAR PRAJAPI

Rural Craft and Engineering SectionMahatma Gandhi Institute of Rural Industrialization

A national Institute Under the Ministry of Micro, Small and Medium Enterprises, Govt of India

Maganwadi, Ramnager, Wardha – 442 00107152 253512, 243350, 253513/FAX - 07152-240 328

Website: www.mgiri.org

http://www.mgiri/

Preface I am please to present the experimental report on “Natural colours of terracotta & its commercial use”. This

experimental work has been conducted in my guidance by Mr Yogesha Prajapti Mr Rajkumar Prajapati and Miss Ujwala Gujar

during her association with the Rural Craft & Engineering Section of Mahatma Gandhi of Rural Industrialization, Wardha.

During India International Trade Faire 2008 the costumers demanded natural coloured terracotta jewellery. For

natural colour of terracotta product we started our experiment with available Indigenous Technical Knowhow of the artisan.

Painting with fine clay on the pots is very old practices. We collected the available fine clay of different regions for different shades

of clays. Now we achieved few shades for composition of terracotta jewellery with natural colours. Few SHGs are already started

the production of natural coloured terracotta jewellery.

We encourage more groups as well as indusial to take up this occupation for their income generation and cultural

development of India.

Best Wishes

(S P Mishra)Senior Scientific OfficerRural Craft & Engg Section

Note: This article is offered free to everyone, with the clear understanding that it cannot be copied for publication/sale under any circumstance, and can be copied for distribution only with attribution to and written permission of the concerned Scientist.

AcknowledgementS

The authors are elevated in expressing their deepest sense of reverence & gratitude to Mr S P Mishra, Senior

Scientific Officer of Rural Craft and Engineering Section, MGIRI for his sincere guidance, sustained interest, painstaking efforts

and constructive criticism throughout the experiment period of this creative and innovative work. Without his valuable

suggestions for improvement at each stage, this work might not have taken its present shape.

The authors are greatly indebted to Dr. T Karunakaran, Director and Mr K V Rao Deputy Director Rural Craft &

Engg Section MGIRI, Wardha for his immense interest during the design experiment conducted.

It is also our immense pleasure to convey thanks to Mr Tapas Dasgupta Principal Scientific Officer of Rural Craft &

Engg Section for his diligent help.

We wish to put on record the help of Mr Eshwer Marskhole of Rural Craft & Engg Section.

Last but not the least authors expressers their gratitude to all the artisan of different cluster those helped for

identifying the local fine clay of their region.

28th Sept. 2009 Yogesh Prajapati Raj Kumar Prajapati

Ujwala Gujar

Natural colours of terracotta & its commercial useIntroduction Terracotta, Terra cotta or Terra-cotta (Italian "baked earth", from the Latin terra cocta) is a clay-based unglazed ceramic. Its

uses include vessels, water & waste water pipes and surface embellishment in building construction, along with sculpture

such as the Terracotta Army and Greek terracotta figurines. The term is also used to refer to items made out of this material

and to its natural, brownish orange color. In archaeology and art history, "terracotta" is often used of objects not made on a

potter’s wheel, such as figurines, where objects made on the wheel from the same material, possibly even by the same

person, are called pottery; the choice of term depending on the type of object rather than the material. Plain unglazed

pottery is often also called terracotta

Pottery has a wide universality and its tradition goes back to span of five millennium. This craft came via Persia, when

Mongal Chengiz Khan had conquered China in AD 1212. The remains of the terracotta objects from the early historical sites

of Mathura, Rajgaht, Kanauj, Kaushambi and Ayodhya reveal the existence of terracotta art in ancient past.Meerut is

famous for its turned and moulded water containers with striking designs of flowing lines and floral patterns. Gorakhpur has

continued the age old Tradition by making decorative and ritual terracotta objects. Amroha pottery used to be thin and

brittle white in colour and ornamented with colours and with gold and silver leaf.In Mathura-Vrindavan, the art of working

in terracotta is of greater antiquity. These terracotta are not only documents of religious sculpture but are important as

documents of early history of art, expression of the artisitic urge of man. The art and technique of blue pottery were

brought to Jaipur, Rajasthan, by the Rajput king Man Singh. It later flourished under the patronage of his great grandson

Maharaja Sawai Jai Sing II.While blue pottery itself originally came to India from Persia and Afghanistan (. History of Pottery,

www. History of Indian Crafts)

Terracotta ColourThe unglazed colour after firing can vary widely, but most common clays contain enough iron to cause an orange, orangish

red, or brownish orange colour, with this range including various colours described as "terracotta". Other colours include

yellow, gray, and pink. Terra cotta is made in several colours, depending chiefly upon the amount of heat it has gone

through. White, pale grey, pale yellow, or straw colour indicate a want of firing. Rich yellow, pink, and buff varieties are

generally well burnt. A green hue is a sign of absorption of moisture, and is a sign of bad material. A glazed surface can be

given to terra cotta if required.

"Another very reprehensible custom is that of coating over the clay, just before it goes into the kiln, with a thin wash of

some ochreish paint, mixed with finely ground clay, which produces a sort of artificial bloom, very pretty looking for the

first year or two after the work is executed, but sure to wear off before long.“

Nature of Clay

As before mentioned, the red clays contain oxide of iron. If this is in considerable proportion (say from 8 to 10 per cent), it

makes them very fusible and difficult to burn successfully. This fusibility is aggravated by the presence of lime, magnesia,

and other impurities, and the resulting terra cotta is not so hard and durable as that from the more refractory white clays.

In some cases the white clay is used with an admixture of oxide of iron just sufficient to make it burn to a good red colour.

ObjectivesThe main objectives are-

• to study natural colour of terracotta available in local region of Wardha.

• to increase the commercial value of terracotta products.

• to develop new products based on the available knowledge.

1 Material Culture

The material remains of this period include pottery, stone artefacts, copper/bronze object and other objects.

Pottery- The pottery that we discover from all the excavated graves is the black-and-red ware. The characteristic types are shallow

tray bowls and deep bowls, both with a rounded base, conical lids with knobs or loops on the apex, pottery ring stands and

larger water pots with rounded bases, etc.

Pottery in Phase I (2500-1800 B.C.) was predominantly handmade, grey or buff-brown. This grey ware is characterized by the use

of bands of red ochre, applied after firing. What is interesting is that some of these pottery forms have applied ring feet and

hollow pedestals which recall the pre-Harrappan types known from Amri and Kalibangan. The other ceramic type of Phase I had

a black or red burnished slip, with a purple painted decoration.

In Phase I1 (1800-1500 B.C.) the red and black slipped wares disappear and new , types occur, These new are perforated vessels,

and vessels with spouts. In ceramic manufacture, the technique of roughening the outer surface of vessels is used, and this

recalls the one employed in the pre-Harappan levels of Baluchistan.

In Phase 111 (1400-1050 B.C.) new ceramic types occur:

a) a grey and buff ware with a harder surface and

b) a wheel thrown unburnished ware with purple paint. This latter type displays affinities with the Jorwe type of Maharashtra,

thus indicating cultural contacts between the southern Deccan and the northern Deccan. The pottery forms are various kinds of

bowls (bowls with lips, lugs and spouts), handled and hollow footed bowls, jars, dishes on stand, perforated vessels, and

spouted vessels. Evolution of Early Society: 2400 B.C. to 1000 B.C.”UNIT 11 CHALCOLITHIC AND EARLY, IRON AGE -11”

Review of literature

Firing Ranges and Natural Clay Colours

Terra cotta is made in several colours, depending chiefly upon the amount of heat it has gone through. White, pale grey, pale yellow, or

straw colour indicate a want of firing. Rich yellow, pink, and buff varieties are generally well burnt.

Stoneware clays like Goldart and most fire clays give an off-white colour at low temperatures, and at midrange and high-fire temperatures

will produce a tan in oxidation and gray in reduction.

Ball clays generally give white at low fire temperatures, and an off-white or gray at high-fire.

Most kaolin's produce white at all temperatures.

Red stoneware clays like Carbondale , Lizella, or Neuman red often tend to be quite coarse, but can still give a good brick-red terra sig that

will survive to high-fire temperatures without fusing into a glaze. Some red stoneware clays may need to be ball-milled before

incorporation into the initial mixture.

Slip clays like Barnard or Blackbird are often too coarse to make a terra sig, but might respond well to ball milling.

For the purposes of black ware firing, a properly-made Redart sig produces a very dense coating, and gives a range of colours from brick

red to jet-black, and any re-oxidized spots will go back to brick red. Ball clay terra sig is slightly more porous, and in a black ware bon firing

can give intense jet-black, and any re-oxidized spots will go to gray or white.

Vince Pitelka , 2006, Super-Refined Terra Sigillata, Digitalfire website.

Experimentation- It was observed that in India after every 20 to 25 kms the water, speaking style and colour & texture of clay changes. So for natural colour terracotta it is very easy to collect the pottery clay from different location and use the combination of different clay colour.

The potters of Wardha area brings good quality clay from Bhandra, Rajura, Temburda, Yawatamal and Pet (Nagpur) area. In this clay they mix locally available black cotton clay and gray colour clay (Bhasuw clay). Black cotton clay have adequate quantity of iron oxide which gives deep red after baking. For deep red terracotta product potters of this region mix 1/3 black cotton clay in good quality pottery clay of brought from outside.

Clay collected from different regions-

1) Black cotton clay of Wardha

2) Gray (bhasuwa) clay of Wardha

3) Pottery clay of Rajura

4) Pottery clay of Bhandra

5) Red colour pottery clay of Temburda

6) Yellow colour pottery clay of Temburda and

7) Red colour pottery clay of Yawatamal

Mixing of different clay for different colour combination- Initially basic colours of different terracotta clay was recorded Then for preparation of colour shed card of following combinations of clays available in local region were made -

Treatment Number

Bhandara clay Rajura clay Black cotton clay Bhasuwa clay

T1 (R1) 1 1 1 -

T2 (R3) 1 1 ½ --

T3 (R8) 1 1 - -

T4 (R9) 1 ½ 1 -

T5 (R10) 1 ½ ½ -

T6 (R2) 1 ½ ¼ -

T7 (R12) 1 - ½ -

T8 (R4) ½ 1 ½ -

T9 (R5) ½ ¼ ¼ -

T10 (R11) - 1 ½ -

T11 (R7) - 1 ¼ -

T12 (R13) 1 1 -

Clay combinations

Treatment number.


T13 (R2 1) 1 1 1 1

T14 R2 18 1 1 1

T15 (R2 3) 1 1 ½ ½

T16R2 14 1 ½ ½ 1

T17 (R2 9) 1 ½ ½ ¼

T18 (R2 2) 1 ½ ¼ ¼

T19R2 15 1 - ½ 1

T20R2 25 1 - - ½

T21 (R2 10) ½ 1 ¼ ¼

T22 (R2 4) ½ 1 ½ ¼

T23 (R2 6) ½ 1 ¼ ½

T24 (R2 8) ½ 1 - ½

T25R2 17 ½ 1 1 1

Treatment number.


T26 (R2 20) ½ ½ 1 ½

T27 (R2 5) ½ ¼ ¼ ¼

T28 (R2 19) ½ - 1 1

T29 (R2 11) ¼ 1 ½ ½

T30 (R2 7) - 1 1 1

T31 (R2 13) - 1 ½ 1

T32 (R2 12) - 1 ½ ½

T33R2 21 - 1 - 1

T34R2 22 - 1 - ½

T35R2 16 - ½ 1 1

T36R2 23 - - 1 1

T37R2 24 - - ½ 1

Treatment number.

Bhandara clay

Rajura clay

Black cotton clay

Bhasuwa clay

Temurda yellow clay

Temurda red clay

T38 (R3 36) 1 1 1 1 1 1

T39 (R3 26) 1 1 - - 1 -

T40 (R3 39) 1 - - ½ - 1

T41 (R3 38) ½ 1 1 1 1 -

T42 (R3 31) ¼ 1 ¼ ¼ 1 -

T43 (R3 35) ¼ ¼ ¼ ¼ ½ 1

T44 (R3 32) - 1 - - 1 1

T45 (R3 27) - 1 - - 1 -

T46 (R3 33) - 1 - - 1 -

T47 (R3 37) - 1 ½ ½ - 1

T48 (R3 29) - ½ ½ ¼ 1 -

T49 (R3 30) - ½ ½ - 1 -

T50 (R3 28) - ½ ½ 1 1 -

T 51 (R3 34) - ¼ ½ ½ - 1

T52 (R3 40) - ¼ ¼ - ¼ 1

Treatment number.

Murum clay

Balaghat clay Rajura clay

Rajashani clay

Bhadrawati clay

Temurda red clay

T53 (R4 5) 1 - 1 - - -

T54 (R4 6) ½ - 1 - - -

T55 (R4 7) ½ ½ - - - -

T56 (R4 1) - ½ ½ - - -

T57 (R4 3) - ½ - - ½ -

T58 (R4 4) - ½ - - - ½

T59 (R4 8) - ½ - - - ½

T60 (R4 2) - - ½ ½ - -

Result & discussion

Natural colours of terracotta

& its commercial use

BALAGHAT CLAY

RAJURA CLAY

BHASUWA CLAY

WARDHA BLACK CLAY

TEMBURDA YELLOW CLAY

TEMBURDA R+Y CLAY

TEMBURDA RED CLAY

BHANDARA CLAY

YAWATMAL CLAY

RESULTSBASIC COLOURS OF DIFFERENT TERRACOTTA CLAY

BIO COLOUR CLAY

Treatment Number

Bhandara Rajura Black clay

T1 (R1) 1 1 1

T2(R3) 1 1 ½

T3(R8) 1 1 -

T4(R9) 1 ½ 1

T5(R10) 1 ½ ½

T6(R2) 1 ½ ¼

T7(R12) 1 - ½

Treatment Number


T8(R4) ½ 1 ½

T9(R5) ½ ¼ ¼

Treatment Number


T10(R11) - 1 ½

T11(R7) - 1 ¼

T12(R13) 1 1

Treatment number.

Bhandara clay Rajura clay Black cotton clay

Bhasuwa clay

T13 (R2 1) 1 1 1 1

T14 R2 18 1 1 1

T15 (R2 3) 1 1 ½ ½

T16R2 14 1 ½ ½ 1

T17 (R2 9) 1 ½ ½ ¼

T18 (R2 2) 1 ½ ¼ ¼

T19R2 15 1 - ½ 1

T20R2 25 1 - - ½

Treatment number.

Bhandara clay

Rajura clay Black cotton clay

Bhasuwa clay

T20 (R2 10) ½ 1 ¼ ¼

T21 (R2 4) ½ 1 ½ ¼

T22 (R2 6) ½ 1 ¼ ½

T23 (R2 8) ½ 1 - ½

T24 R2 20 ½ ½ 1 ½

T25 (R2 18) 1 1 - 1

T26 (R2 5) ½ ¼ ¼ ¼

T27 (R2 19) ½ - 1 1

Treatment number.

Bhandara clay


Bhasuwa clay

T21 (R2 10) ½ 1 ¼ ¼

T22 (R2 4) ½ 1 ½ ¼

T23 (R2 6) ½ 1 ¼ ½

T24 (R2 8) ½ 1 - ½

T25R2 17 ½ 1 1 1

T26 (R2 20) ½ ½ 1 ½

T27 (R2 5) ½ ¼ ¼ ¼

T28 (R2 19) ½ - 1 1

T29 (R2 11) ¼ 1 ½ ½

Treatment number.

Bhandara clay


Bhasuwa clay

T30 (R2 7) - 1 1 1

T31 (R2 13) - 1 ½ 1

T32 (R2 12) - 1 ½ ½

T33R2 21 - 1 - 1

T34R2 22 - 1 - ½

T35R2 16 - ½ 1 1

T36R2 23 - - 1 1

T37R2 24 - - ½ 1

Treatment number.

Bhandara clay

Rajura clay

Black cotton clay

Bhasuwa clay

Temurda yellow clay

Temurda red clay

T38 (R3 36) 1 1 1 1 1 1

T39 (R3 26) 1 1 - - 1 -

T40 (R3 39) 1 - - ½ - 1

T41 (R3 38) ½ 1 1 1 1 -

T42 (R3 31) ¼ 1 ¼ ¼ 1 -

T43 (R3 35) ¼ ¼ ¼ ¼ ½ 1

(R3 26) (R3 27)

Treatment number.

Bhandara clay


Bhasuwa clay

Temurda yellow clay

Temurda red clay

T44 (R3 32) - 1 - - 1 1

T45 (R3 27) - 1 - - 1 -

T46 (R3 33) - 1 - - 1 -

T47 (R3 37) - 1 ½ ½ - 1

T48 (R3 29) - ½ ½ ¼ 1 -

T49 (R3 30) - ½ ½ - 1 -

T50 (R3 28) - ½ ½ 1 1 -

T 51 (R3 34) - ¼ ½ ½ - 1

T52 (R3 40) - ¼ ¼ - ¼ 1

(R3 27) (R3 28) (R3 29)

Treatment number.

Murum Balaghat Rajura Rajashan Bhadrawati Temurda red

T53 (R4 5) 1 - 1 - - -

T54 (R4 6) ½ - 1 - - -

T55 (R4 7) ½ ½ - - - -

Treatment number.

Murum Balaghat Rajura Rajashan Bhadrawati Temurda red

T56 (R4 1) - ½ ½ - - -

T57 (R4 3) - ½ - - ½ -

T58 (R4 4) - ½ - - - ½

T59 (R4 8) - ½ - - - ½

T60 (R4 2) - - ½ ½ - -

R2 23

R4 4

R3 33

CHINA+TEMBURDA YR4 1

YAWTMAL

RESULTSSELECTED COLOURS OF TERRACOTTA

NATURE COLOUR TERRACOTTA JEWELLERY

Colour: Nature clay colour

Size- Standard sizePrice- 150/- per piece

TERRACOTTA NECKLACE SET UJD-03

ATTACHMENT

NECKLACEClay beads - Ball beads

6mm-10nos 3mm-11nos 2mm-5nos

Rice shape beads 8mm-9nos

moon shape beads13mm-11nos

Melon shape beads9mm-7nos

Neck Chain/rope - Black cotton necklace thread

EARRINGClay beads - Ball beads

4mm-4nos drum shape beads

15mm-2nos rice shape beads

8mm-2nosEarring hooks - Brass wire with golden

colourNo-22




ATTACHMENT


2mm-16nos moon shape beads

13mm-4nos Melon shape beads

9mm-10nos10mm-2nos


flower shape beads8mm-2nos



2mm-2nos Rice shape beads


15mm-2nos flower shape beads


colourNo-22




ATTACHMENT


4mm-2nos5mm-4nos9mm-2nos12mm-2nos

Drum beads10mm-2nos

Flower shape beads8mm-3nos

Neck Chain/rope-Black cotton necklace thread Glass beads -Black round shaped beads,

blue kite shaped beads EARRINGClay beads - Ball beads 12mm-2nos Earring hooks - Brass wire with golden

colour No-22Glass beads - Round shaped beads,

Kite shaped beads




ATTACHMENT


2mm-5nos Cone shape beads leagth13mm,dia8mm-4no flower shape beads

8mm-2nos6mm-2nos


Glass beads –Green rectangle shaped beadsKundan – Brown &silver EARRINGClay beads - Ball beads



colourNo-22Glass beads –Green rectangle shaped beadsKundan -Brown & silver




ATTACHMENT


6mm-2nos Flat pear shape beads

10mm-12nos Barrel shape beads

8mm-2nos Flower shape beads

8mm-2nosGlass beads - 5mm-12nosNeck Chain/rope - Black cotton necklace

thread EARRINGClay beads - Ball beads

6mm-2nos Barrel shape beads

8mm-2nos Flower shape beads

8mm-2nosGlass beads – 5mm-2nosEarring hooks - Brass wire with golden

colourNo-22




ATTACHMENT



13mm-4nos Melon shape beads

9mm-10nos10mm-2nos


flower shape beads8mm-2nos



2mm-2nos Rice shape beads




colourNo-22

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Natural Colours of Terracotta & Its Commercial Use

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