Colors that fade

The oil colors makers rate less lightfast, classic pigments that fade in tints and glazes, lightfast stand-ins, and how to test a tube yourself.

Most oil colors sold today are rated very lightfast, and many will outlast the canvas. A handful of classic colors are less durable: they look fine on the palette but can slowly lose strength in light, most visibly in pale tints and thin glazes. Here's what those are, the lightfast pigments that do a similar job, and how to check a tube for yourself.

Pigments known to fade, and lightfast stand-ins

The number on each stand-in is how many single-pigment tubes of it are rated very good or better.

Alizarin crimson PR83

A synthetic version of the old madder dye, made since 1868. At full strength it holds up reasonably well, but thin glazes and pale mixtures with white lose color noticeably in strong light. Most makers rate it fair (ASTM III).

Found in 20 tubes on Pigfolio. Lightfast stand-ins:

PR177 Anthraquinone Red8 PR264 Pyrrole Rubine3 PV19 Quinacridone Violet / Rose / Red32 PR179 Perylene Maroon5

Rose madder genuine NR9

The natural madder lake that alizarin replaced. Ratings differ from maker to maker; pale tints and thin glazes are the most likely to fade.

Found in 3 tubes on Pigfolio. Lightfast stand-ins:

PV19 Quinacridone Violet / Rose / Red32 PR122 Quinacridone Magenta12 PR209 Quinacridone Red6

Aureolin PY40

A transparent cobalt yellow from the mid-1800s. Most oil makers rate it well, but independent tests have been mixed: it can fade or turn olive-brown over time, especially in thin layers.

Found in 7 tubes on Pigfolio. Lightfast stand-ins:

PY150 Nickel Azo Yellow8 PY154 Benzimidazolone Yellow H3G4 PY128 Disazo Condensation Yellow4

Lithol rubine PR57

A low-cost azo red found here in a few student colors, usually mixed with an orange. Royal Talens rates these ++, which it describes as 25–100 years under museum conditions.

Found in 6 tubes on Pigfolio. Lightfast stand-ins:

PR254 Pyrrole Red11 PR255 Pyrrole Scarlet6 PR188 Naphthol Red HF3S4

Tartrazine lake PY100

A food-dye yellow on a lake base, used here in a student sap green. Sap green was once a plant lake, and blends sold under the name still vary a lot in lightfastness.

Found in 1 tube on Pigfolio. Lightfast stand-ins:

PY129 Green Gold (Azomethine)8 PG36 Phthalo Green (yellow shade)15 PY150 Nickel Azo Yellow8

Van Dyke brown NBr8

A natural brown made from peat or lignite. Older versions were known to fade and stay soft in thick layers; ratings for today's tubes vary, and many makers sell a Van Dyke brown hue mixed from iron oxides and black instead.

Found in 5 tubes on Pigfolio. Lightfast stand-ins:

PBr7 Natural Iron Oxide (Siennas, Umbers)64 PR101 Red Iron Oxide (Mars / Burnt Sienna)77

What the ratings mean

Lightfastness is how well a color keeps its strength and hue when exposed to light. Makers test it by exposing painted samples to sunlight or to lamps that imitate it, then measuring the change.

ASTM I–V (the American standard, tested under ASTM D4303): I is excellent, II very good, III fair, IV poor and V very poor. The standard for artists' oil paint (D5098) accepts only I and II.
Blue Wool scale (used mostly in Europe): 1 to 8, where each step lasts about twice as long as the one before. 7–8 roughly matches ASTM I, 6 matches ASTM II, and 4–5 matches ASTM III.
Makers' own scales: Winsor & Newton's AA, A, B and C (permanence, which also covers reactions with other pigments), Holbein's stars, Royal Talens' +++ to +. Each tube page shows the maker's rating as published.

Pigfolio sorts these into three tiers: excellent, very good and fair or lower, plus not rated when a maker doesn't publish one. Ratings describe the paint at normal strength. Mixed with a lot of white or thinned to a glaze, there's less pigment to absorb the light, so any change shows sooner.

Test a tube yourself

On a strip of primed canvas or board, paint each color three ways: at full strength, thinned to a glaze, and mixed with about ten parts titanium white.
Label each sample with the brand, color name and date (the batch number too, if it's on the tube), and let it dry for a week.
Cover half of every sample with something opaque, such as card or aluminum foil taped down firmly. Keep a second strip in a dark drawer as a reference.
Put the strip behind a sunny window (south-facing in the northern hemisphere, north-facing in the southern) for at least three months, ideally through a summer. Window glass filters some ultraviolet, which is close to how paintings usually hang.
Uncover it and compare both halves in daylight. The tint is usually the first to show any change. No change after a summer is a good sign, though not a guarantee for decades.

Light isn't the only thing that changes paint. Some whites and pale colors yellow slightly in the dark as the oil ages; that's the binder, not the pigment, and it usually fades again in light.

If you love a color rated fair

Use it at full strength rather than in pale tints or thin glazes.
It's fine for studies, sketches and practice, where longevity matters less.
Hang finished work out of direct sunlight; that helps every painting.
Many makers sell a lightfast version under a similar name, such as “permanent alizarin crimson”. Check the pigment code on the label to see what's actually in it.