The girih tradition
These twelve are named for places the app's own patterns come from. Each entry says what that craft actually does with colour, and what this scheme takes from it.
Two pairs are one craft each. Fes and Alhambra draw on the same five colourants doing the same five jobs, in Morocco and in Granada; Herat and Samarkand are the same Timurid work, with artisans moving between the two courts. The dark lines differ too: Morocco and Granada draw theirs in manganese with iron, Anatolia in chromite black, and cut-tile mosaic draws none at all, since what reads as a line there is the mortar between the pieces.
Isfahan
Haft rangi tile · Iran, 17th century
The Persian capital moved to Isfahan at the end of the 1500s, and the great square there was tiled in haft rangi, "seven colours". A stonepaste square is covered in an opaque tin-white glaze, several coloured glazes are laid side by side on it, each field fenced off by a greased black line so they cannot bleed, and the whole tile is fired in one pass. It replaced cut-tile mosaic across most of the work, because one painted square covers what mosaic needs dozens of hand-cut pieces to cover.
That white glaze is why this scheme's cream ground is right: a haft rangi tile really is coloured figures on a warm white field. The fills take five of the canonical seven — lead antimonate yellow, cobalt, white, copper turquoise and hematite red — and the line is the manganese-and-iron black the greased resist leaves behind.
Herat
Timurid tile · Afghanistan, 15th century
A vast mosque and madrasa complex was begun at Herat in 1417 and pulled down in 1885 to clear a line of fire from the citadel; five of its twenty minarets survive. Three techniques carry the colour: glazed bricks set among plain ones, monochrome tiles cut into shards and bedded in mortar, and several glazes painted on one square inside a greased line.
The ground is fired brick, because banna'i sets its glazed bricks among plain ones and the field is the wall itself. The fills lead with copper turquoise, which identifies Timurid work on sight, is one of the three original glazes, and is what the analysis of the surviving dome reports. Behind it sit cobalt, tin white, a lead-stannate yellow and the light green that joined the palette late.
Samarkand
Timurid tile · Uzbekistan, 14th and 15th century
Timur ruled from Samarkand, and the mausolea along the Shah-i Zinda accumulated for a century after him. The colour set is tight enough to work as a dating tool: the British Museum dated a group of these tiles on the strength of one combination, white with turquoise and cobalt blue.
So this scheme is blue on blue, which is how the Shah-i Zinda and the Gur-i Amir read. Its fills are that triad — white, turquoise, cobalt — with a lead-stannate yellow and a paler turquoise beside them. The line is pale rather than dark, because cut-tile mosaic draws no contour at all: what reads as a line is the mortar between the pieces.
Bukhara
Suzani embroidery · Uzbekistan, 19th century
Bukhara's buildings are brick before they are tile. Its oldest mausoleum is decorated entirely in unglazed brick, in basket-weave and herringbone bonds with no glaze at all; turquoise tile arrives later, and the great turquoise domes later still.
So this scheme is the city's embroidery rather than its buildings. Suzani is silk worked on an undyed cotton ground, which is the cream here, and its dyes are madder for the red, indigo for the blue, delphinium for the yellow, and pistachio galls with iron for the black-brown of the line. Central Asian architectural glaze has no red in it at all, which is one reason the needle rather than the kiln is the right reading of these seven.
Fes
Zellij · Morocco, 14th century
The Marinids were the first to run zellij across whole wall surfaces, in the madrasas of Fes in the 1300s. The order of work is the thing to know: a tile is glazed and fired first, and only then struck to shape face-down with a small adze-like hammer. The glazes are tin for white, cobalt for blue, copper for green, manganese with iron for black-brown, and iron for yellow.
Zellij draws no line at all. Cut pieces are laid face down and coated with plaster, so the seam is whitish, and the dark in the craft is manganese with iron, which is what the line here is. The five fills are copper green and its deep value step, tin white, iron yellow, and the cobalt blue a Marinid panel leads with.
Cordoba
Umayyad stone, brick and glass · Spain, 8th to 10th century
Cordoba has no glazed-tile tradition, and that has to be said first. Its colour comes from three places: the hypostyle hall's horseshoe arches, with voussoirs alternating red brick and white limestone; the mihrab, finished in 965 in glass mosaic sent from Constantinople, gold leaf sealed under a thin pane; and the city's ceramic signature, verde y manganeso, copper green and manganese purple-black on honey-coloured clay.
This scheme reads the building: brick red and limestone cream for the arches, gold for the mihrab, and the green and blue the mosaic sets beside that gold. The line is the manganese-and-iron brown of al-Andalus, the dark that verde y manganeso draws its strokes in.
Alhambra
Alicatado · Spain, 13th and 14th century
Nasrid Granada. Alicatado is built from small flat pieces cut to geometric profiles, glazed one by one, often bevelled on the back so they seat against each other in the panel. The glazes are lead and tin-opacified and fired in an oxidising kiln at around 900 °C, which is what gives the honey colour: iron, confirmed as fired that way.
The warm end of this scheme is the iron family, and the green is copper. The fifth fill is manganese black, because black and green on white is the documented starting point of alicatado at this site. The line is the manganese-and-iron brown the craft's dark really is, the same one Marrakech uses.
Marrakech
Zellij on a pisé city · Morocco, 12th to 16th century
Marrakech is built of reddish rammed earth, some nineteen kilometres of it in the ramparts alone. Its earliest surviving architectural glaze is narrow and specific: red earthenware under an opaque greenish-white glaze, carrying an inscription in dark purple.
This is the best fit of the twelve, and the only one here with its own ground and line, both both its own. The ground is the pisé the city is built of. The dark brown line is what manganese and iron fire to. Four of the five fills are documented glazes — copper green, iron yellow, cobalt blue, tin white — and the fifth is the red of the terracotta body and the wall itself, which is where red comes from in this craft rather than from the kiln.
Konya
Seljuk cut tile mosaic · Turkey, 13th century
Thirteenth-century Konya was the Seljuk capital, and its madrasas are sheathed in mozaik çini: monochrome glazed sheets cut to shape, laid face down and joined with plaster. Tiles for this use were made with a thinner glaze and a looser body, so they could be scraped and trimmed to fit a curved vault.
So the field is dark, as the Karatay dome is, and turquoise leads: it is the most characteristic Seljuk colour and the most heavily loaded glaze in the published analysis. Beside it sit a deeper turquoise, cobalt, the dark aubergine manganese fires to, and gold leaf, which is real here — cut to pattern, brushed on over the fired glaze and refired low. The line is chromite black.
Iznik
Underglaze-painted fritware · Turkey, 16th century
Iznik ware is fritware, mostly quartz with clay and frit, under a lead-soda glaze over a white slip, and that white is warm rather than paper white. The colours arrive on a datable sequence: cobalt alone from about 1480, copper turquoise around 1520, sage green and a pale purple in the 1540s, and then the colour the ware is known for, a bole red laid on thick enough that it stands in slight relief under the glaze.
All five fills are real colourants and the warm white is right. The line is chromite black, whose melting point is too high for it to bleed into the molten glaze, which is exactly why Iznik drawing is so sharp. The five fills are the ware's whole range rather than one moment of it: sage green belongs to the 1540s and the bole red to 1560 and after, by which time a bright emerald had taken the green slot.
Bursa
Cuerda seca · Turkey, 15th century
The Yeşil Külliye at Bursa, built between 1419 and 1424, is where cuerda seca first appears in Ottoman building, worked by tilemakers brought from Tabriz. Its mihrab arch and ceiling are described as white, yellow, shades of blue and green, with gilding; its wall tiles as dark blue, dark green, turquoise and black.
Green with gold is the combination Bursa is known for, and it is documented at the building itself. The fills take the deep green of the glaze, the gilding, the white, a second green and the turquoise the wall tiles carry, and the line is chromite black, whose melting point keeps it from bleeding into the glaze around it.
Plaster
Carved gypsum · the app's own neutral
Not a place and not a palette. Carved plasterwork is real and is everywhere in Islamic building, under a different name in every language: gypsum laid on in coats, marked out, then carved with iron tools while it is still damp, or cast from moulds so one unit can be repeated.
The thing to know is that it was painted. Excavated tenth-century dado panels were originally bright yellow, red and blue, and the colour vanished within hours of being exposed to air; analysis of Alhambra stucco finds lapis, malachite, cinnabar and gold leaf. So this is not a craft's palette but unpainted or weathered plaster, which is what the app uses it for, and on those terms its near-identical creams are right. Its line is a plaster grey-brown, because a carved surface draws no contour: it has a shadow.
Other traditions
These sixteen come from crafts outside Islamic geometry altogether: tin glaze, porcelain enamel, mosaic glass, lustre, fresco, vellum. Each was built from the colourants that craft actually used, with the research done first.
- Delft
- Puebla
- Triana
- Deruta
- Arita
- Jaipur
- Pecs
- Ravenna
- Antioch
- Pompeii
- Kells
- Kintsugi
- Dancheong
- Celadon
- Sancai
- Benjarong
Delft
Tin-glazed earthenware · Netherlands, 17th century
Potters in Delft copied Chinese export porcelain onto local buff earthenware, hiding the clay under a glaze made white with tin oxide. The white is warm rather than paper-white.
Almost all of it is one colour. Cobalt is painted under the glaze at different dilutions, from a near-black violet-blue for the contour line down to thin grey washes, so a piece reads as a single blue in several strengths. The workshops could fire yellows, greens and purples, and gave them up when blue and white took over. The scheme follows that: five strengths of one cobalt, with the contour line as the line.
Puebla
Talavera · Mexico, 16th century onwards
Spanish potters brought tin-glazed earthenware to Puebla in the 1500s, where it met local clay and local taste. Certified Talavera is still made to a legal standard: the glaze has to craze, and has to be milky-white rather than pure white.
Its colour is unusual in being a closed list. Six are permitted, all from minerals ground by hand: blue from cobalt, yellow from antimony, green from copper, black from iron, plus orange and mauve. The scheme uses all six, with the iron black as the line.
Triana
Azulejo, cuerda seca and arista · Spain, 15th and 16th century
Seville's Triana quarter, on the far bank of the Guadalquivir, was a tile-making centre from the late Middle Ages. Two techniques carry it: cuerda seca, where a drawn line of grease mixed with manganese keeps the glazes from running together, and arista, where the dividing ridges are pressed into the soft clay from a mould.
Unlike most tile crafts it does not paint on white. The ground is the red-buff Seville clay, and tin white is one glaze among five: white, a honey melado from iron, copper green, manganese brown-black and cobalt blue. A tile usually shows three to five of them, with the dark manganese line holding the design together.
Deruta
Maiolica · Italy, 15th and 16th century
A maiolica town in Umbria, working a white tin glaze over earthenware in a warm ivory, with wide empty areas left around the design.
Its colour arrived in stages: two pigments to begin with, manganese purple-brown and copper green, then cobalt, then the full run of blues, greens, yellows, oranges, black and brown. Deruta's own trick is lustre, a third firing in a starved kiln that leaves a metallic film on the surface. Silver gives a gold-yellow, copper gives a ruby red, and the scheme uses both.
Arita
Imari porcelain · Japan, 17th century
Porcelain clay was found near Arita early in the 1600s and Japan began making its own porcelain, much of it shipped out through the port of Imari.
Here the colour is layered by firing temperature. Cobalt goes onto the raw clay and survives the hot glaze firing; everything else is enamel painted on top and fired cooler, with the gold last of all. The Kakiemon body is a warm milk-white left mostly bare on purpose, so the colour reads as a few sharp marks on a wide empty field. The signature is the triad of cobalt blue, iron red and gold.
Jaipur
Blue pottery · India, 19th century
Blue pottery reached Rajasthan from Persia by way of Kashmir and settled in Jaipur. There is no clay in it at all: the body is a dough of ground quartz, ground glass, fuller's earth, borax and gum, closer to Egyptian faience than to pottery.
Six oxides were available, and the craft is known for two of them. Cobalt draws the outline and copper turquoise fills in beside it, on a slightly grey white, and a typical piece carries only two or three colours. The scheme keeps to that pair rather than using everything the kiln could do.
Pecs
Zsolnay eosin · Hungary, 1890s
The Zsolnay factory in Pécs developed eosin with a chemist and showed it off at the Budapest exhibition of 1896.
It is the one craft here whose colour will not hold still. Eosin is a metallic lustre laid over an already-fired dark glaze and fired again in a starved kiln, leaving an iridescent film whose hue changes as you move: deep green one way, gold the next. A piece usually carries one eosin colour and its own shift, so the scheme is built as four steps of that green-to-gold travel plus the ruby, on a dark base.
Ravenna
Byzantine mosaic · Italy, 6th century
The churches of Ravenna hold the best-surviving Byzantine wall mosaic, laid when the city was the western seat of the empire.
The gold here is not an accent, it is the background the figures stand in: beaten gold leaf on a cake of glass, sealed under a thin fused disc. The coloured glass around it is made with cobalt for blue, copper for turquoise and for red, lead compounds for yellow and green, manganese for purple. Stone does the rest, pale limestone for skin and porphyry for imperial purple. The scheme puts the gold field in the ground.
Antioch
Roman polychrome floor mosaic · 2nd to 4th century
Roman floor mosaic in colour, as laid at Antioch, Pompeii, Rome and across North Africa. It is named for Antioch and not for Ostia on purpose, because Ostia's own floors are black and white.
The palette is set by the quarry trade rather than by the painter. Nearly every colour is a named stone shipped in from somewhere: giallo antico for yellow, rosso antico for red, verde antico for green, porphyry for purple, bardiglio for blue-grey, flint and basalt for black, with glass filling in where no stone will do. That is why Roman colour looks muted and a little dusty. Four to eight colours in a floor is typical.
Pompeii
Fresco · Italy, 1st century BC to 79 AD
Wall painting on lime plaster, burnished to a sheen, buried by Vesuvius and dug out again.
Two things are worth knowing about its colour. "Pompeian red" is not a pigment: it is a modern trade name that runs together true cinnabar, imported and expensive enough to be billed to the client separately, with cheap local red ochre. And an unknown share of that red was yellow until 79 AD, because heat turns yellow ochre into red hematite and the eruption did exactly that across the town. The palette as we see it is partly the volcano's work.
Kells
Insular manuscript illumination · Ireland, around 800
The Book of Kells, an illuminated gospel book painted on calf vellum, now in Dublin.
Its colour is remarkable for what it does not contain. There is no gold leaf in it and no lapis lazuli. The blue long taken for imported Afghan lazurite turned out under Raman analysis to be indigo. The whole book runs on six or seven pigments: indigo, red lead, orpiment yellow, a green mixed from the first two, carbon and iron-gall black, and gypsum white, on a warm cream.
Kintsugi
金継ぎ, lacquer repair · Japan, from the 16th century
Not a palette and not a ware, a repair. A broken bowl is rejoined with urushi lacquer dusted with gold powder, and the seam is left standing proud instead of being hidden.
So the gold is a line and not a field, which is the one thing the app can match exactly: the strapwork takes the gold, and the ground and fills take the pot, five values of a dark iron glaze running to the rust-orange a tenmoku goes where it thins over an edge. A girih lattice is regular and designed where a kintsugi seam is one accident made precious, so what carries across is the gold and the dark pot it is set into.
Dancheong
단청, painted woodwork · Korea, Joseon dynasty
The painted beams and brackets of Korean temples and palaces, in colours laid down by convention rather than chosen building by building.
The colour starts with a base coat rather than with a hue: a celadonite grey-green called noerok under everything else, or an iron red-brown on pillars and sun-facing surfaces. On top of it go red lead, gamboge yellow, copper green, azurite blue and white, outlined in ink black. Korea's five cardinal colours look like a match for the app's five fills and are not one, since two of them are black and white, so the scheme is built from what a building actually carries.
Celadon
Goryeo 청자 with 상감 inlay · Korea, 12th century
An iron glaze fired in a starved kiln to the blue-green the period called bisaek, kingfisher colour.
It is a three-colour craft and the scheme is built as one. The design is carved into the half-dry clay and the hollows filled with contrasting slip, a white clay and an iron clay that fires black-brown, so the inlay is the drawing and the line at once. Two of the five fills here are declared steps of the glaze itself rather than invented hues: adding colours would mean inventing a traditional palette that never existed.
Sancai
三彩, lead-glazed earthenware · China, Tang dynasty
Earthenware under coloured lead glazes, much of it made for tombs. The name means "three colours".
The three are amber from iron, green from copper, and a cream that is no colourant at all but the white body showing through a clear glaze. Cobalt blue exists but was imported and costly, and manganese brown turns up less often, so the scheme keeps those two as the rare ones. The glazes are poured on and allowed to run into each other, and that running is the look, so the dark here is a manganese glaze standing in for an edge the ware never draws.
Benjarong
เบญจรงค์, overglaze enamel · Thailand, 18th and 19th century
Enamelled ware for the Siamese court, at first ordered from Chinese kilns to Thai designs. The name comes from the Sanskrit for "five colours".
A benjarong design is named by its pattern together with its background colour, and that background is dense enamel rather than bare porcelain, so the scheme sits on a deep blue. Gold goes on after the enamels in a third and cooler firing, and no Thai source counts it among the five, so here it takes the line instead of a colour slot. In practice a piece carries three to eight colours despite the name.