PAINTING WHITE – 2

Post 485  –by Gautam Shah

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During 1930-50s Paint shops used to offer Oil-bound Distempers (OBD) and combination of Zinc pastes and double-boiled Linseed oil, for household painting. These were mixed with pigment pastes for shade creation. Post 1950s ready mixed oil paints or General purpose enamels (GP) became popular. But than paints’ shops had to stock several tins of different measures, for each of the shades and varieties (oil paints, distemper paints, flat and egg-shell plastic paints). And to match a desired shade, it was necessary to buy small bottles or vials of concentrated pigment pastes called tinters and top up an available shade or create one from a white.

Paint Shop of earlier era

There were two whites available, a ‘super-whitewith some form of ‘optical whitener or brightener, an ‘opacifier’ or colourants like blue or violet, and pure stuff called base-white, without any additives. Few lay people were aware of the later variety, or considered it to be some inferior stuff due to its less romantic name (super white versus base-white), and discounted price.

Zinc paste-based paints and General purpose enamels had linseed oil or its alkyd resins as the chief film forming material. The linseed has a tendency to oxidize and turn yellow over the age. This began to change due to strong demand from manufacturers of white-goods (consumer goods painted white such as ovens, fans, washing machines, refrigerators, etc.) for long-term non yellowing finishes. This led to use of non yellowing oils for resins, and new generation formulations of Urethane, Amino resins and epoxies. The same innovations began to percolate to home-paint markets. From 1960s Plastic polymer-based emulsion paints (called Latex paints in USA) began to be available. This offered non-yellowing white paints.

Shade Card

Titanium Dioxide as a whitest pigment had few technical problems of paint formulations, but these were initially solved with use of Zinc and Lithopone as additives. Oil paints in glossy and flat varieties, and Plastic Paint with, sheen, egg-shell-matt and flat varieties now were offered as one or two coat systems. This high hiding-covering was due to excellent pigment grinding-dispersion in machines like attritors that replaced ball and roller mills.

United States Capitol west front

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Paint markets are now radically changed. Paints manufacturing companies depend on shops to match the colour shades. The shades are created from basic, and few vials of ground pigments, which inject exact-micro quantity of colours into range of base formulations. The base formulations, include nearly clear to several types of white paints. White bases have natural shades of white pigments, and some have whitening-opacifiers. A white base is used for light tints, but not more than 100 ml paste can be added for darker shades to avoid loss of gloss or the effect on drying time. A neutral, pastel or mid-base contains lesser quantity of white pigment and is used for creating darker colours. And a clear base is used (it may contain white powders of low refractivity or extenders, but is free of high refractivity white pigments), for very deep colours. Some manufacturers use this base to add little sheen to matt paint.

Whites are affected by surroundings and show many variations

Whites are affected by smallest amount of additive colourants. These colourants may come from residues of earlier colour in brushes or rollers, any loose particles on the surface to be painted and thinners (solvents and water). Some additive colourants, if not thoroughly mixed, begin to darken the colour shade over brushing or rolling. Extra ordinary care is required in selecting, buying, mixing and using, white and ‘off-white’ shades. Shops have a file of colour shade cards, which are rarely fresh. The shade card viewing must be done in natural light, as it is affected by the surroundings and type of illumination. Shop computer calibrated and mixed shades, are not necessarily exactly right as per the shade card or as per your need.

A colour shows many variations at different angles of viewing and so colour matching must be done perceiving it from as many positions > Pic by https://www.flickr.com/photos/horiavarlan/4271993197

One of the best ways is to buy a small trial pack, and apply it on two different walls (preferably at right angles), at the site location. Once a right shade is achieved, leave some quantity (see the next paragraph) in the trial pack for master batching and matching.

HOW to mix a white shade with very light tinge of other colours at home? Buy the most appropriate white-base out of several ones available at a paint shop (usually 2-6 varieties). Now separately mix the concentrated tint to small quantity of white-base, with shade as close matching to your desire. Such faint tinges of colours are very difficult to visually perceive. So place a drop of experimental mix over the quantity left in trial pack. Your shade will be either darker or lighter, but easily perceptible.Mixed Whites

Most plastic emulsion paints now have a ‘Thixotropic’ compound, which gives a heavy, butter like false viscosity to the paint, to prevent separation or settlement of heavier phases or solids. Stirring is required to reconvert the stuff to a temporary liquid phase. Plastic paints come with good odours, to suppress the unpleasantness of paints, but one need not judge a paint on that count.

Color Blue Church Terrace Architecture White

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ART COATINGS

Post 432 – by Gautam Shah

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Lascaux2

Coatings are thin surface finishing techniques. A thin film is achieved by using a material that is in a liquid state or is convertible into a liquid phase. A coating may or may not have a colourant, but on drying achieves various degrees of transparencies. Coatings are applied to entities to alter the appearance, improve the tangibility and to provide a protective cover. Historically, however, coatings have been used for illustration and decorative effects.

The discovery of mixing dishes suggests that liquid pigment mixed with fat was also used and smeared with the hand. The subtle tonal gradations of colour on animals painted in the Altamira and Lascaux caves appear to have been dabbed in two stages with fur pads, natural variations on the rock surface were exploited to create the effects of volume.

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The simplest way of marking cave walls was to make finger-traces in the soft layer of clay covering the rock. Lime stone walls were engraved and filled in with iron oxide (hematite, or ochre), or the black pigment as manganese or charcoal. These materials were usually available locally. Analyses of pigments, reveal the use of extenders such as talc or feldspar, to increase the bulk of pigments. It also shows traces of animal and plant oils, used for binding. The pigment in paste form was applied with fingers, and also tools like animal-hair brushes or crushed twigs. Lumps of pigment discovered on cave floors may have been used as crayons, but since they do not mark the rock well, they were more likely to be sources of powder. Colour was often sprayed, from the mouth or through a tube. A network of ladder, supports and scaffolding was used to reach the ceilings and upper portions of walls. Light was provided by hearths, or portable burning torches.

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Primitive coatings were daubing of clays, minerals, charcoal, lamp blacks often mixed with mediums such as water, tallow, vegetable excretion and juices, urine, blood, bitumen. Binding mediums were employed to fix the mineral or colourant particles on the surface. Some of the binding mediums were evaporative and worked only as a `leveller’ for particulate matter. By 6000 BC, in China, calcined (fired) mixtures of inorganic compounds and organic pigments and binding mediums (vehicles) were prepared from gum arabic, egg white, gelatin, and beeswax.

Some oily mediums though superior in fixing and longer lasting, but collected dust on aging. Oil mediums became darker in colour due to oxidation, or just peeled off. Some of the mediums were destroyed due to fungus and algae. Later little more complex substances such as starches of rice and maize, pine wood extracts, egg albumin, bees wax, hydrated limes, gypsum, etc. were used.

PREHISTORIC ART FORMS

There are basic TWO sets of Arts. Fixed arts are built-forms, wall murals and architectural embellishments. These could have been part of either exterior and interior environments. Portable arts, comprise of objects or artefacts. These usually remained in protected environments. Fixed arts were largely painted and scratched or engraved, but portable arts had, at least in initial periods, natural finishes by way of selection and production processes.

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Portable arts consist of wide variety of object forms and material combinations. Compared to the fixed Arts the objects are smaller in size. The portable objects show all, the surface treatments, embellishments and coating applications. The objects of this category show greater integration of all the three interventions and greater detail or involvement. Large number and wide variety of objects have been preserved and recovered even from regions where Fixed Arts entities have not survived. Portable arts’ objects are smaller and personal hobby or a family craft creation. The colour and surface quality were matter of choice or discoveries through innovation in production.

Paulnabrone

Fixed Arts entities that have survived are surface treatments or renderings through show painting, scratching, engraving and daubing methods. On the other hand, the surviving built-forms, if considered as art-forms, represent technological milestones of material handling, supporting and construction planning. Fixed arts were large scale or important societal activities, involving entire community by way of voluntary participation or forced labour. The involvement of the community was for seasonal or occasional rituals. The leader, conductor or priest of the ritual and the team were the select few experts who initiated and updated the (art) entities over and over again. Such art-forms indicate occupation or interventions of several generations, as much as for more than 300 years.

Bradshaw rock paintings

Portable Art objects are incidental that is the availability, shape, size, colours, texture, etc. define the range of treatments. Many times the purpose it will serve evolves during the process of treatments. Such objects show material combinations. many different finishes were achieved, by change of forms and exploiting the tools. Material processes like heating, singeing, sintering, baking, beating, shaping, cutting, chopping, grinding, drilling, etc., were also used in farming and cooking. It was one seamless manner of learning.

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The materials were stones, precious stones, metal nodules, mineral and other colourants, woods, grasses, twigs, hides, leathers, skins, furs, hairs, shells, teeth, horns, bones, ivory, raw clay objects, baked clay ceramics, seeds, fruits, etc.

The objects formed were totems, body adornments, tools, implements, ritual and burial objects, cooking utilities, toys for children, amenities and dwelling embellishments.

Collier_de_Penne

These were exchanged, gifted to others or offered in rituals. The objects began to have consistent expressions. The varied metaphors, passing from one generation to other, ultimately became abstract. Coins, plaques, seals, etc. represent multiple conversions of expressions like a language.

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Fixed Art objects like built-forms, though functional utilities were built for community and for political purposes.

The public use entities were irrigation facilities, forest clearance, dykes, bridges, walks or passages, drinking water resources, community surround structures, security amenities and storage arrangements. These were not ‘decorative arts’ but symbolized technological innovations. Some like burial stones and dolmen had items of personalization.

Cave_Paintings_Bhembetika_(22)e

Fixed Arts objects like wall arts show skills of surface preparation, rendering or painting and surface finishing. These creations also show art of surface preparation by way of grinding, etching, daubing, engraving and colourant application. Wall-arts exist in odd narrow corners, at very high elevations, tall ceilings, day time dark corners and in nearly inaccessible places. The effort must have required support structures, bridges, scaffolds, illumination and ancillary works to protect the creations from moisture.

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RED Colours of ancient times

Post 430 – by Gautam Shah

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Red is the most fascinating colour in history. It is the colour of kill, blood and life. It was prominently used in prehistoric cave art. It was made with red Hematite or iron oxide, as red ochre. It is one of the oldest pigments and has lasted well for more than 70000 years. Red ochres are very stable colourant unaffected by alkaline or acidic effects, moisture or UV exposure. The red ochre is available in many colour variations, in almost all regions of the world, and usually at surface level. The minerals in the form of rocks, lumps or dust form can be ground to fine powder form.

Cochineal insects crushed

Red oxide or Red ochre colours of the primitive age were not the most brilliant colours if one were to compare it with some of the synthetic red pigments (cadmium, chrome, rubine, etc.), we use today. But in absence of the ‘brilliant reds’ the Red Ochre was a magical red. Primitive man, however had some ochres that were brighter then others. The brilliance of red was enhanced by mixing, or with topping with wax or oils.

Natural dyes on Skeins

The early civilizations used ‘red colours’ for different purposes such as body painting, ceramic painting, dyeing of leathers and fabrics. Root extract of the Rubia or Madder plant was used in ancient Egypt for colouring textiles. A red colourant made from an insect exudate called Lac, gave the term ‘Lake’ (a transparent dye-based colour). In Italy during the post mediaeval periods, the Lac was considered very expensive pigment. Henna leaves and madder roots were mixed with alum to create red shades. Another source of red colour was from insects Cochineal and Kermes vermilio. The Romans used a bright red or vermillion pigment made from a natural mineral called cinnabar. A warm ruby-red resinous exudation of Calamus draco was used by illustrators. Red lead or Lead tetroxide pigment was widely used in Persian and Indian miniature paintings. It was also used in European art by name minium. Sindoor is a brilliant red colour powder used by Indian (Hindu) women, on their forehead and for hair parting. It was Vermillion, but being a toxic material is now produced by reacting Turmeric with Alum or Lime.

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Sindoor Tikka Powder Hindu Women use in on forehead

In India, red dyestuffs were used from antiquity. These were plants of kampillaka (Mallotus phillippinensis), pattanga (Caesalpinia sappan), jauka (a species of Oldenlandia), and animal substances like indragopa (cochineal). The Sappan wood tree (Caesalpinia sappan from Asia and Brazil) based, red dyestuff is called Brazilian.

Vermilion Pillars

Red Ochre powders were placed with dead bodies (Neolithic) or heaped on burial mounds (S. India). The word magic =Zauber in German, =taufr in Old Norse, or =teafor in Anglo-Saxon >> all meaning Red Ochre.

Red Lanterns Shanghai

Red colour is associated with Egyptian God, Set. Set was a god of storms, unpredictable and associated with deserts and foreign places, meaning with chaos and danger. The word ‘desert’ has derived from the Egyptian ‘dshrt’ or ‘deshr‘ or ‘deshret‘=red place or Red Land. Red Ochre was sourced from desert lands. ‘The hieroglyph for red is the hermit ibis, a bird which, unlike the other ibis of Egypt, lives in dry areas and eats insects and small creatures. Writers of Egyptian papyri used a special red ink for nasty words.

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Red palette has offered a vast number of shades and chromatic variations. Red has been used as space making colour of walls and earth or floors, but not for aeriform figures like flying angels, heavens, skies or ceilings. It has been used in murals, paintings, statues, architectural interiors, manuscripts, dresses, adornments, foods, funerary, etc. Red has been a colour of piety, royalty as much as of death and fear. Colours have been codified but named differently in various parts of the world, roughly the time sequence was black, white, red, green, yellow and blue. Some of the ancient Reds were: Iron oxide (hematite), Ochres (burnt-calcined), vermilion, cinnabar (natural mercuric sulfide), realgar (natural arsenic sulfide), minium (heated white lead), natural dyes (madder, kermes, brazil-wood), sandarac. words.

Red Colours in Egyptian Art

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PRIMITIVE COATINGS # 1

Post 411 – by Gautam Shah

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Coatings have been used for decorating and suffusing objects and surfaces for the past 60000 years. These were used for several purposes such as to add a colour, impart a protective layer, ‘plaster’ a surface, imprint a pattern or create an identity signage.

Stone and other artefacts requiring coating or decoration

A primitive person had many objects that could receive the coatings. These objects were natural, reformed or produced ones. The objects had different sizes, shapes and surfaces. The surfaces had characteristic textures, porosities, base-colours and patterns (grains, patches, stains, etc.).

Korea Neolithic age pot

The objects were own body skins, hairs, and nails. Animal products like teeth, animal hides, furs, bones, and teeth. Minerals’ items like sands, clays, stones, rocks, precious stones, and sea shells. Plant items such as dry leaves, grasses, seeds, dried fruits, fibres and woods. The manufactured range of items included clay products, ceramics and metals.

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The surfaces were prepared to receive the coating. Hides were cleaned and shaved by heavy rubbing. Body surfaces were oiled to receive the colourants. Walls were washed and wetted prior to coating application. Bones were ground to remove the sheen and make surface slightly rough and absorbent. Stones and woods were polished or scrapped. Raw and baked clay products were re-fired after coating. Leaves were rolled and flattened and dehydrated at the green stage by burying in layers of ash or sand.

The coatings’ materials were of natural origins, such as available off the ground, or from animals and plants. But the coating materials were processed by filtering or sieving, washing, cleaning, decanting, boiling, singeing, and sintering.

The act of coating was intentional, done with a sure purpose. But the resultant effects were wondrous, something that gave a new purpose to the artefact. The art of drawing and the technique of coating, was seamless process of magic. A process to express, what the postures, gestures or spoken language could not do.

Coating techniques and materials of the primitive age are still being used in many situations, and so continue to be relevant. Blood is perhaps the earliest colourant, as a fresh liquid it has very rich colour. It was a colour to represent the vibrancy of life and metaphorical power over the kill. Blood, however, is biologically degradable material, dries to a darker shade, and has very weak colour-integrity. Wood coal is a dry colourant, easy to handle. It requires a textured base for ‘rubbing-in’ or a binding liquid to form an applicable paste. Carbon (Lamp) black -a deposition collected over burning fat or oil, is much better due to oil content. Whites were procured from metallic oxides and carbonates. Lime is most common everywhere. Other whites included talc, whiting and barytes. Iron oxides are equally common, and have many different hues (such as yellow ochres, browns of sienna and umber, red and black oxides). Oxides are very stable, and have ‘deep’ saturated colours.

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Black Carbon of Soot or Lamp black

In this palette of colours, the notable absence was Blue and Green. Blue and green appeared very late in the form of Lapis lazuli and Malachite (copper carbonate hydroxide). Brilliant Red that could represent the fresh blood, and Brilliant Pink of the meat were also absent. Purple was nearly unknown. The absentee colours were sourced from plant juices and natural dyes, but had poor colouring strength or low opacity (transparent), sun light fading, and biodegradable colours so were not long lasting.

Sprayed colours

The primitive colourants were mostly of dry powders or soft rocks. These had no binding capacity. Mineral pigments were heavily rubbed on the surface to trap them in the micro cavities of the surface. Liquid juices could absorb into the surface. Some form of binding material or technology was needed. Water has temporary binding capacity and can be used as a carrier agent. To fix colours plant oils, mutton fats, fish oils, etc. waxes, and plant latexes were used. These substances except the wax were ‘non-drying’ and remained wet for a long time. The wet surface attracted dust and trapped insects. The oily substances biologically deteriorated, and on oxidation turned darker in colour.

Proteins-based materials like blood, eggs, milk, urine, and starches were also used as binding materials. Plant and insect exudates or natural gums had binding properties but were highly hygroscopic (affinity with water) materials. Plant milks or latexes, like materials, were also used. Wax was used to mix with pigments and as a protective layer. Wax and natural Creosote were used to protect wood and leather surfaces.

Number of cementing substances were used for coating or plastering. Mud plasters, slaked lime and Pozzolana (volcanic) ash, were materials that had binding properties. Colouring these substances, or coating over it (fresco style) required large quantities of materials, or concentrated pigments. Lime when mixed with a colourant imparted a white shade creating a ‘pale’ effect. Pozzolana had darker colour so made the colourant several shades darker. Plastering and daubing, were frequently used to prepare a better surface for a wall painting. Primitive binding materials can be categorized like, 1 Materials that are water reducible, water resistant and hygroscopic, 2 Air drying and non drying, 3 Non water-based materials.

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The primitive age craft of coating can be summed up as 1 Surface preparation, 2 Application of the coating, 3 Applying tonal variations or shades, and 4 Covering the surface with water protective coat, usually of oils or other transparent materials. The process of application of colourants or the coating system was adapted to the nature of the base surface, as much as to the type of colourants and binders.

Twig brushes

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Drawing points and crude shading brushes

Primitive coating applications are varied. The simplest way of marking cave walls art was to make finger-nail traces in the soft layer of clay covering the rock. Lime stone walls were engraved and filled in with iron oxide (Hematite, or ochre), or the black pigment such as the manganese or charcoal. Analysis of cave wall art pigments, reveal the use of extenders (dull or low opacity powders) such as talc or feldspar, to increase the bulk of pigments. The coating also shows traces of animal and plant oils, used either for binding or as a protective covering. The pigment in paste form was applied with fingers, and also tools like fiber pads, animal-hair brushes or crushed twigs. Lumps of pigment discovered on the floor of caves were perhaps used as crayons, or were grinding onto colour powder. Colours were often sprayed, from the mouth or through a tube. A network of ladder, supports and scaffolding was used to reach the ceilings and upper portions of walls. Light was provided by hearths, or portable burning torches. The coated surfaces were ground to achieve a sheen on the surface or re-coated with a protective layer of egg-whites, oils or fats.

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The earliest known use of colourants dates back to 70000 years, whereas Cave wall art is about 40,000 years or older. BC. Lascaux, an underground cave, 17300 BC, located in SW France, has walls and ceilings, decorated with some 1,500 engravings and about 600 paintings in shades of yellow, red, brown, and black. The subtle tonal gradations of colour on animals painted in the Altamira and Lascaux caves appear to have been dabbed in two stages with fur pads, natural variations on the rock surface were exploited to create the effects of volume.

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NATURAL IRON OXIDE PIGMENTS 4 # SIENNA and UMBER

Post 409 – by Gautam Shah

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Death of the Virgin. Louvre, Paris. By Caravaggio

An artist palette and building designers’ vocabulary invariably includes few rich earth colours such as red oxide, ocher, raw sienna, burnt sienna, raw umber, burnt umber and Indian red. These colours in various intensities, transparencies and reductions with white create a language that cannot be matched by synthetic pigments. The iron oxide colours are sun fast, and remain stable on alkaline (masonry or lime) and acidic (metal) surfaces. Browns colours cover a wide visible spectrum, ranging from yellow, orange, to red. The shades are also named using composite adjectives, like red-brown, yellow-brown, dark-brown, etc. Modern day browns derive by mixing green (blue with yellow) and red, or orange and black. Red colouration is linked to the presence of hematite, and yellow colouration to the presence of goethite.

Rembrandt van Rijn Self-Portrait (1659)

Rembrandt

Like the other earth colours, such as yellow ochre and umber and sienna are clays containing iron oxide, called limonite, which offers yellowish colour. These colours are a range of different colours. All standards fail to agree on precise shade for them.

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Red oxide usually contains about 70% Fe2O3 . Sienna is a brownish yellow containing about 60% Fe2O3 with some quantity of manganese oxide. Umber is a greenish brown containing some 45% Fe2O3 and 15% MnO2. Umber is named after a department in Central Italy where it was first tested. Umber of good quality, called Turkish Umber, is found on the island of Cyprus. Numerous deposits of colouring earths occur in various parts of the world.

Vieja friendo huevos by Diego Vel

Earth colours Sienna and Umber, are mix of limonite with some amounts of manganese oxide, and so both are darker then ochers. Senna is darker, more towards orange and so thought of as reddish, compared to Umber that is closer to yellow and thought of as brown. Sienna has a higher content of manganese which makes it greenish brown or darker brown. Raw Sienna is transparent and warmer whereas Raw Umber is opaque. Raw Sienna when calcined becomes richer and darker as the burnt sienna. Raw Umber becomes the rich deep or dark brown as burnt umber.

Johannes Vermeer Milkmaid in Umber shades

Sienna was mined originally mined near Arcidosso, formerly under Sienese control, in southern Tuscany. It was also called terra rossa (red earth), terra gialla, or terra di Siena. Umber is linked to Umbria in mountainous region in central Italy, and so called terra di Ombra or Umbria. Ombra literally means ‘shadows’, for the purpose for which it was used, shadows or for shade toning other colours.

Caravaggio flagellation Musée des Beaux Arts, Rouen

The creative exploitation umber for creating dark shades happened during the baroque period, in the chiaroscuro (light-dark) style of painting. It was the palette of Caravaggio (1571-1610) and Rembrandt (1606-1669). This nearly ended during 19th C, when Impressionists dazzled with modern brilliant synthetic pigments, rebelled against the dark and dirty umber and other earth colours.

The Calling of Saint Matthew by Caravaggio (1599-1600)

NATURAL IRON OXIDE PIGMENTS -3 # Ochres

Post 408 –  by Gautam Shah 

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Ochres in Towns

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Ochre is an iron oxide pigment of natural and synthetic sources. Ochre are coloured soft deposit of clays often with mixed layers or pockets harder crystalline iron ore. Some of the best yellow ochre ’s are mined at Roussillon, Southern France. Here the mineral formations are naturally stained with colours to provide a wide variety of earth or natural iron oxide colours.

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ocher_rocks_rock_ocher_roussillon_places France

The Greek word ochros, for Ochres describes it to a pallid or pale yellow, but natural ochers are brilliant colours. Ochres have a colour range that varies from yellow to deep orange or brown, due to the hydrated iron oxide. This is unlike the Red oxide which is from hematite powder, a form of iron oxide (Fe2O3). An ochre containing a large amount of hematite has a reddish tint, and is known as ‘red ochre’. The dominant yellow colour of ochre is due to the mineral limonite. Ochres are of two kinds, one with an argillaceous or clayey basis has richer colours, whereas the other with a calcareous base is slightly of ‘flatter’ colours. The nature of the associated minerals affects the colour, such as calcareous varieties have brownish-red and dark-brown shades, and aluminous types offer red and violet tints.

 

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Different colours of Ochre pigments are extracted from different veins, and then mixed to obtain specific shades. Other shades are created by roasting (‘burnt’ or calcination), and dehydrating the mineral clays.

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Yellow Ochre is a very ancient pigment. It is without any trace of green. The oxide colours are called Earth colours, due to their richness, brightness and warmth. Ochres are mixed with high refractive whites like Lime (or zinc, titanium dioxide), or low refractive ‘extenders’ such as the barytes to achieve, respectively, high opacity or translucency.

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Manuscript Cover India in Ochre colours

In Ancient Greece, red-ocher was called miltos, (hence Miltiades red-haired or ruddy). In Athens when assembly was called, everyone was supposed to attend it, and failure to attend it incurred a fine. To prevent people loitering around slaves swept the open space of the Agora with ropes dipped in miltos . It was also known as raddle, reddle or ruddle. In Ancient Egypt, the ochre was often used in place of gold, which was considered to be eternal and indestructible. It was used for painting tomb interiors in place of toxic orpiment (an orange-yellow coloured arsenic sulphide mineral). Ochre was used for painting women’s faces. Romans used the yellow ochre to to represent gold, skin tones, and as a background colour in their paintings such as the murals of Pompeii.

Egyptian Ochre colours

A rational process for refining ochre pigment was developed by the French scientist from Roussillon province of France, Jean-Étienne Astier (1780s). He washed the clay to separate the grains of sand from the particles of ochre. The decanted and dried ochre was crushed, sifted, and ground as the pigment. Best of the qualities were used for artists’ colours.

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Ochre robed Sadhus sitting on the Vishnu Temple of Kathmandu’s Durbar Square, Nepal Wikipedia Image by us Koljonen (Dilaudid)

NATURAL IRON OXIDE PIGMENTS – 2 # Red Oxides

Post 407 – by Gautam Shah 

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The first primitive colours, ranged from yellow to brown to red to near black. These came from three basic materials that are Oxides of Iron, Calcium and Carbon, respectively for Red-brown, White and Black colours. The ‘earth colours come from inorganic minerals like, Iron oxides with its various stages of hydration, and Manganese oxides.

Iron Oxide Red

The chief earth colour constituent, Red hematite powder, a form of iron oxide (Fe2O3), was found scattered around the remains at a grave site in a Zhoukoudian cave complex near Beijing. The site has evidence of habitation as early as 700,000 (?) years ago. The hematite might have been used to symbolize blood in an offering to the dead. It was also used in powdery form, 164,000 years ago by the caveman of ‘Pinnacle-Point’ (caves in South Africa), possibly for body painting. Hematite residues are also found in old graveyards from 80,000 years ago. Hematite as a mineral, is coloured black to steel or silver-gray, brown to reddish brown, or red. The various forms hematite show variegated rust-red streaks or bands. The word Hematite is a Greek word haimai that alludes to red colour of the blood.

Iron bands

Hematite is harder than pure iron, but very brittle. In steel-gray crystals with metallic lustre, hematite is called specular iron ore whereas thin scaly ones are known as micaceous hematite. Most hematite occurs in a soft, fine-grained, earthy mineral form of red ochre or ruddle. Red ochre has been used for body coating and cave art painting. It is now used in paint pigment, for primers, and as a polishing medium or rouge for finishing plate and spectacle glasses.

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Venetian red

Rusted Iron colours

Limonite (hydrous ferric oxide) ranges from yellow to brown. These are known as Ochre, Sienna, and Umber. Ochre is clay-coloured with hydrated iron oxide. Tuscany, famous for its ‘Terra di Siena’, is a hydrated iron oxide with silicates and aluminates that endow some transparency to the pigment (Silicates and Aluminates are extenders, with a lower refractive index, so add to the bulk and increase the transparency). When limonite is heated for calcination, the water part is removed to form ‘Burnt Sienna’.

Oxide colour painted Barrackpore Railway Station North 24 Parganas W Bengal India > Wikipedia Image by Biswarup Ganguly

Venetian red is a slightly darker than a scarlet red, but less intense colourant from purer form of hematite. It was also called Sinopia due to its origin from Sinop in North Italy. Similar colourants (of pure hematite) were called Ocra rosso or red ochre. Due to its pure quality, the pigment, when mixed with white, produced a likeable pink. The red Sinopia or Sinoper and its lime mixed pinks were used in Italian Renaissance paintings for body tones. It formed the major ingredient in the colourant called Cinabrese. Sinopia was used for the cartoon or under-painting for a fresco.

Sinopia

Red oxide colours were not perfect red colours. These had either a yellow-brown tinge or blackish shade. The colour available in dyeing of fabrics gave that desired perfect red. Dyes were not preferred for paintings or wall art for two reasons, One, dyes were soluble in water and had lesser opacity (‘covering or hiding capacity’) Egyptians used the root of the Rubia, or madder plant, to make a dye, later known as alizarin. This was mixed with whites powders of low refractivity, and used as a pigment (known as madder lake, alizarin or alizarin crimson).

Ajanta Caves, India Oxide based earth colours

Ajanta Caves, India Oxide based earth colours

The earth colours have been extensively used in Ajanta and wall arts at several places. The early works show range of earth colours mixed with white and only occasionally greens. The mixing of ochre (in absence of pure yellows) produced darker or olive green effect. Pure pinks were absent.

Buddhist Monks on pilgrimage varied shades of earth colours Wikipedia Image Credit: Tevaprapas Makklay

In India the Earth colours have also been known as Bhagawa and Gerua. Bhagawa is brownish or more towards Ochre, whereas the Gerua is a red iron oxide colour. Both the colours show regional variations. Bhagawa colour has been colour of attire for Hindu and Buddhist monks. Geru or Gerua colour is used on water and plant pots and buildings. It is used as a decorative coating with lime white, on lower sections of tree trunks. Temples in South India have Gerua coloured stripes on external face. Buddha adopted the colour for own robes, because at that point of time it was the colour of prisoners’ dress. Sikhs adopted the Bhagawa colour, but now their choice leans more on purer synthetic orange or saffron, than earthy colour Bhagawa.

Varanasi (Benaras) India Gerua coloured Durga temple Image by Henk Kosters https://www.flickr.com/photos/68556734@N00/741206048

For translators, transliteration of colour, is always problematic. Colour names are closely linked to their cultural interpretations. So, for the Indian classical story of Nala and Damayanti, “the king loses the kingdom in gambling, and retires to forest. His wife queen Damayanti renunciates the world to accept the asceticism. She starts wearing Bhagawa or earth-brown coloured clothes”. A Russian translator perceives the mood, but reinterprets for his own culture and makes Damayanti wear Black, the colour of widowhood. Today, Western reporters claim the Gerua or Bhagawa to be colour of Saffron, and link it to Hinduism.

Typical Iron Oxide Red Shades

  •     Hex: #6E0303
  •     RGB: 110, 3, 3
  •     CMYK: 0, 0.973, 0.973, 0.569
  •     HSV: 0, 97, 43

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