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Ultramarine Ash
#4166F5 · click to copy
Cool
HEX
#4166F5
RGB
65, 102, 245
CMYK
73%, 58%, 0%, 4%
Pigment
PB29 (degraded/mixed)
Lightfastness
Good (II)
Pigment & Material
PB29 (degraded/mixed)
Synthetic
The mineral residue of lapis lazuli after the extraction of lazurite. Much lower purity than true ultramarine — grey-blue rather than deep blue. Used as an economical substitute.
Origin & History
Ultramarine ash represents the economics of Renaissance pigment use — even in wealthy workshops, the finest ultramarine was reserved for the most important passages (the Virgin's robe, the sky in the central panel). Secondary grades of the same pigment were used for backgrounds and less visible areas.
Also Known As
Ultramarine Violet
Blue Ash
Smalt Ash
Psychology
Quiet, contemplative, and secondary. Ultramarine ash is blue without insistence — it supports rather than dominates. Its historical role as the background colour, the support for more important colours, gives it a certain modesty that the pure ultramarine lacks.
In Culture
The practice of reserving the finest, most expensive pigments for specific areas of a painting reflects the contractual nature of Renaissance art patronage — patrons often specified in contracts which colours must be used and where. The hierarchy of pigment quality mirrors the hierarchy of spiritual importance in religious paintings.
Natural Sources
Historically, "ultramarine ash" referred to the lower-quality washings of lapis lazuli — the paler, less pure blue produced in later washing stages of the lapis purification process. It was cheaper than true ultramarine and used for less important areas of paintings.
Making It Yourself
Mix ultramarine blue (PB29) with titanium white and a very small amount of raw umber to produce a slightly greyed, less saturated version.
Alternatively: mix ultramarine with a touch of burnt umber for a warm, muted blue.
Alternatively: mix ultramarine with a touch of burnt umber for a warm, muted blue.
Art Movements
Renaissance (secondary pigment use)
Baroque
Famous Works
Used in backgrounds and less important passages of Renaissance paintings where true ultramarine was too expensive
Frescoes
ash pigments used for larger areas
Available As
Not a standard commercial colour — approximate with any muted blue-grey.
Farrow & Ball — Lulworth Blue No.89
Benjamin Moore — Blue Ash 2129-40
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Colour data compiled with AI. Spot an error or have more to add? Leave a Note — ekphra reviews and updates.
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