Short answer
Compare them by what causes the colour, not by country. The same red iron oxide colours Dumfries sandstone, Goan laterite, Mexican tezontle and Ethiopian scoria; the same lime chemistry makes brick yellow in London and Milwaukee. Grouped that way the similarities cross continents and the differences fall inside single cities — Edinburgh alone appears four times in this dataset with four different stones.
Sorting the dataset's material records by mechanism puts unlikely neighbours together. Red iron oxide accounts for the red sandstone that reached Edinburgh and Glasgow by rail, the reddish laterite of the Konkan coast, the oxidised volcanic scoria called tezontle in the Basin of Mexico, the haematite-rich scoria into which the churches of Lalibela were cut, and ordinary red brick. Yellow-brown iron oxyhydroxide accounts for Bath's weathered stone, Salamanca's golden patina and Jaisalmer's yellow limestone. None of these places borrowed a colour from another. Iron is abundant in the Earth's crust, and wherever it meets air and water it settles into the same few oxides.
The pale records divide into two mechanisms that can look alike. Some materials simply hold little iron: Portland limestone, Malta's Globigerina limestone, Lisbon's Lioz, the Tyndall stone of the Canadian prairies, and buff bricks made from low-iron fireclay. Others are pale because calcium carbonate changes what the iron does in the kiln — London stock brick and Milwaukee's cream brick — or because the visible surface is lime itself, as in limewashed Pembrokeshire, Zanzibar and Bermuda. A pale town is thus not evidence of a particular geology; it may be evidence of a coating, and the stone beneath a white wall can be dark.
Several of the best-known place colours are imports or exports. Portland stone went from Dorset to London's monuments and, in the twentieth century, to buildings and war graves abroad. Welsh slate left Gwynedd for roofs on several continents; UNESCO records that by the late nineteenth century the district produced about a third of the world's roofing slates. Falun's pigment painted farms across Sweden. Imitation travelled too: Pembrokeshire's guidance notes that town houses there were rendered, lined out to resemble stone blocks and often painted cream to look like Bath stone. A colour can be characteristic of a place without originating there.
Of the 57 records in the dataset, 30 speak for a whole city, region or country; the rest describe a single site, a group of buildings or a district. The fine-grained records are where a national summary would mislead. Edinburgh contributes a pale buff Carboniferous sandstone, a pinkish-grey specimen from one quarry, a formation that runs from white to red, and imported red Permian stone. Glasgow's centre is recorded as both cream and red. London appears once for Portland stone on public buildings and once, with the South East, for yellow stock brick. A single swatch labelled 'Scotland' or 'London' would have to discard most of this.
The table groups what Colourwise could locate and read, which is not the same as what exists. The 21 countries represented lean heavily towards Britain and western Europe, because geological surveys and heritage bodies there publish openly in English. East and South-East Asia, most of Africa and South America are thinly covered or absent. Timber building is represented only through Swedish red paint, and vegetation and landscape colour not at all. For several records the mechanism family is inferred from a source's colour words, not from mineral analysis, and each of those is flagged in its caveat. Read the counts as a map of the evidence, not of the world.
| Mechanism | Records | Countries | Places recorded |
|---|---|---|---|
| Red iron oxide (haematite) | 11 | 7 | Hailes Quarry, Edinburgh; South Edinburgh; Edinburgh; Glasgow; Mexico City and the Basin of Mexico; Lalibela; Goa and the Konkan coast; Marrakesh; Britain; Toulouse; Falun |
| Yellow-brown iron oxyhydroxide (goethite, limonite) | 8 | 6 | Bath; The Cotswolds; Salamanca; Jaisalmer; Sentier des Ocres, Roussillon; Siena; Umbria (disputed); Old City of Sana'a |
| Pale rock or clay with little iron | 8 | 6 | London; Edinburgh; Paris; Lisbon; Valletta and the Maltese islands; Winnipeg and the Canadian prairie cities; Jerusalem; Britain |
| White lime coating | 5 | 3 | Pembrokeshire; Suffolk; Scotland; Stone Town, Zanzibar; St George's, Bermuda |
| Mixed silicate crystals | 3 | 3 | Aberdeen; Porto; Madrid |
| Dark minerals or fine-grained dark rock | 3 | 3 | Florence; Melbourne; Gwynedd, north-west Wales |
| Lime or magnesia in fired clay | 2 | 2 | London and the South East; Milwaukee |
| Sheet metal | 1 | 1 | Paris |
| Scope of the statement | Records | Share |
|---|---|---|
| Single site or quarry | 5 | 9% |
| A group of buildings | 9 | 16% |
| District | 13 | 23% |
| City or town | 14 | 25% |
| Region or island | 10 | 18% |
| Country | 6 | 11% |
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
Colourwise analysisModerate evidence
In Colourwise's place-colour dataset, red iron oxide is the recorded mechanism for building materials in at least five countries on four continents, including Scottish Permian sandstone, Western Ghats laterite, Mexican tezontle and Lalibela scoria.
Based on: Counted by Colourwise from the dataset's material records grouped on mechanism family; see the first table on this page. The family is assigned by Colourwise from each source's description.
Caveat: A count of located records, not a census of the world's buildings; for some rows the mechanism is inferred from colour words.
Source: Building stones in Edinburgh from the Permian and Triassic New Red Sandstone of Dumfries & Galloway and Cumbria; IUGS Heritage Stone: Western Ghats Laterite; IUGS Heritage Stone: Tezontle volcanic scoria; IUGS Heritage Stone: Lalibela Basaltic Scoria
FactStrong evidence· Gwynedd, Wales· Late nineteenth century
The Slate Landscape of Northwest Wales produced about a third of the world output of roofing slates and architectural slabs by the late nineteenth century.
FactStrong evidence
Portland limestone, quarried on the Isle of Portland in Dorset, has been used since the seventeenth century for buildings of national significance in London and since the eighteenth century internationally.
ConventionStrong evidence· Pembrokeshire, Wales
Town houses in Pembrokeshire were often rendered smooth, marked to resemble stone blocks and painted cream to look like Bath stone.
Source: Traditional Pembrokeshire Buildings: Exterior Colour Schemes
Colourwise analysisModerate evidence
Of the 57 records in the dataset, 30 describe a whole city, region or country and the remainder a single site, a group of buildings or a district.
Based on: A count of the scope Colourwise assigned to each record from what its source actually covers; see the second table on this page.
Caveat: Scope is an editorial judgement about each source's reach.
Source: Building stones of Edinburgh: introduction; World Heritage List (open dataset whc001)
Reviewed 6 October 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.