Key to the Paint Ratings

PG7chlorinated copper phthalocyanine (1927; 1938)winsor green BSWinsor & Newton2093453011178-28,8
PG7phthalocyanine greenM. Graham1503464122184-58,8
PG7phthalo green BSDaniel Smith0553459021179-28,8
PG7phthalo greenRembrandt6754359034176-18,8
PG7cupric green deepMaimeriBlu3244352034177-28,8
PG7phthalo greenDaVinci2684462122175-18,8
PG7blockx greenBlockx2634458113175-38,8
PG7phthalocyanine greenUtrecht1674355031174-37,8
PG7phthalo greenRowney Artists3614350031175-27,8
convenience greens made with PG7, listed in hue angle order from blue green to yellow green
PG7+PY150chlorinated copper phthalocyanine + nickel azomethine yellowhooker's green deepRembrandt623235803216107,8
chlorinated copper phthalocyanine + zinc oxide + benzimidazolone lemonwinsor emerald
[discontinued in 2005]
Winsor & Newton0542427032160-133,6
PG7+PY151chlorinated copper phthalocyanine + benzimidazolone yellowpermanent green lightM. Graham1302363032160-77,8
PG7+PY3chlorinated copper phthalocyanine + arylide yellow 10Gpermanent green lightUtrecht1612352041159-167,7
PG7+PY3chlorinated copper phthalocyanine + arylide yellow 10Gpermanent greenDaniel Smith0222344030158-137,8
PG7+PY175chlorinated copper phthalocyanine + benzimidazolone lemonpermanent green deepMaimeriBlu3403243024158-97,8
PG7+PY154chlorinated copper phthalocyanine + benzimidazolone yellowpermanent greenRembrandt6622357032157-77,8
chlorinated copper phthalocyanine + arylide yellow 10G + quinacridone rosehooker's green #2 [dark]Rowney Artists3544336031153-55,6
PG7+PY3chlorinated copper phthalocyanine + arylide yellow 10Gpermanent green lightDaniel Smith0471335042148-156,7
PG7+PY153chlorinated copper phthalocyanine + nickel dioxine yellowhooker's green #1 [light]Rowney Artists3534360031140-124,4
PG7+PO49chlorinated copper phthalocyanine + quinacridone goldhooker's greenMaimeriBlu3253360023139-147,8
PG7+PY110chlorinated copper phthalocyanine + tetrachloro-isoindoline yellowhooker's greenM. Graham1081363041139-57,8
PG7+PY3chlorinated copper phthalocyanine + arylide yellow 10Gphthalo yellow greenDaniel Smith1242328032135-187,7
PG7+PO62chlorinated copper phthalocyanine + benzimidazolone orange H5Gsap greenM. Graham1741361041132-117,8
PG7+PY138chlorinated copper phthalocyanine + quinophthalone yellowvivid greenRowney Artists0471331042131-127,8
PG7+PY150chlorinated copper phthalocyanine + nickel azomethine yellowsap greenRembrandt6232355032131-127,8
chlorinated copper phthalocyanine + arylide yellow G + synthetic yellow iron oxidepermanent green #1Holbein2662133101128-105,6
PG7+PY42chlorinated copper phthalocyanine + yellow iron oxidesap greenDaVinci2773345211128-17,8
chlorinated copper phthalocyanine + nickel dioxine yellow + transparent red iron oxidesap greenRowney Artists3754362031123-107,8
PG7+PO49chlorinated copper phthalocyanine + quinacridone goldsap greenDaniel Smith0433351120119-128,8
PG7+PBr7chlorinated copper phthalocyanine + natural iron manganese oxideterre verteSchmincke5164131122107-28,8
chlorinated copper phthalocyanine + nickel azomethine yellow + quinacridone roseolive greenRembrandt620234803210307,8
PG7+PY42chlorinated copper phthalocyanine + synthetic yellow iron oxideolive greenWinsor & Newton033403811199-47,8
chlorinated copper phthalocyanine + nickel dioxine yellow + pyrrole carmineolive greenRowney Artists363436903195+32,4
TOP 40 PIGMENT   Phthalocyanine green PG7 (blue shade) is a very lightfast, transparent, heavily staining, dark valued, moderately dull blue green pigment, one of the most widely used modern industrial colorants, offered by 60 pigment manufacturers worldwide. The ASTM (1999) rates its lightfastness in watercolors as "excellent" (I); all manufacturer and independent tests agree. PG7 is twin to the yellow shade of phthalocyanine green (PG36) and cousin to the phthalo blues (PB15); like them, its tinting strength is very high.

Phthalocyanine is the most widely used green pigment in watercolors and is the green anchor for many brand specific convenience greens (discussed below). It undergoes a moderately large drying shift, both lightening and losing saturation by 15% to 20%. Unlike the phthalo blues, phthalo green shows almost no hue shift from masstone to undertone. There are many excellent mixing complements for phthalo green, including quinacridone maroon (PR206), perylene maroon (PR179), pyrrole scarlet (PR255), pyrrole red (PR254), cadmium red (PR254) — almost any scarlet or middle red, intense or dull, will do nicely. The average CIECAM J,a,b values for phthalo green [blue shade] (PG7) are: 31, -51, 1, with chroma of 51 (estimated hue purity of 52) and a hue angle of 178.

If you're interested in the phthalocyanines as a pair, then there are four brands — Winsor & Newton, Daniel Smith, MaimeriBlu and Rembrandt — that currently offer both PG7 and PG36, all with a comparable hue spacing (about 17 degrees), chroma and tinting strength. However, most artists choose only a single phthalocyanine green (if any) for their palette, and PG7 tends to be the preferred choice of manufacturers and artists. The Winsor & Newton and MaimeriBlu paints have good chroma and tinting strength but the Daniel Smith and M. Graham paints are darker valued, which I prefer to mix moody dark blues with quinacridone violet (PV19) or dioxazine violet (PV23). The Daniel Smith phthalo green BS bronzes in heavy applications. Utrecht's phthalo green is a pale, almost pastel formulation that holds its color in tints and has a lower tinting strength that does not overwhelm other paints (a design point consistent throughout Utrecht's watercolor line). Both the Utrecht and MaimeriBlu phthalo greens are less staining, making them generally easier to work with. The Blockx blockx green is flat and dull.

Both phthalo greens PG7 and PG36 are notable for their intense tinting strength and strong tendency to stain paper, attributes that arise from their small particle size. They easily stand up to or even dominate other strongly tinting pigments such as the quinacridones, dioxazine violet or pyrrole red, and they are an excellent choice as the foundation paint when nonstaining pigment glazes are to be laid down and then partially lifted or blotted away. The drawback is that phthalo green must be applied exactly where you want it on the first pass — make a mistake, and you'll be scraping paper to remove it!  

Convenience Greens. Next we enter the jungle of specialty greens mixed with PG7 or PG36 ... an overgrown and treacherous profusion of paint. Many of these convenience greens were developed as substitutes for fugitive or antiquated green pigments, including copper greens, and these fusty old pigment names contribute to a labeling free for all in green paints: the marketing name tells you nothing about what you're buying.

The lightfastness of PG7 is no guarantee that convenience green mixtures with a yellow paint will be equally lightfast. In fact, convenience greens are often the most impermanent paints in any watercolor line. I recommend you do your own lightfastness tests on any convenience greens you use.

Nearly all convenience greens are a mixture of a green and a yellow or yellow orange pigment, which locates the hue somwhere between middle to yellow green. Why don't artists just mix these greens themselves? Many do. But greens can be hard to mix, and repeatedly mixing the same green hue gets tedious very quickly. However, the real benefit of convenience greens is that they reliably locate a specific hue, value and saturation of middle or yellow green, which can then be modulated with a little added color from any other paint on the palette. This home base mixing strategy creates a cluster of related greens centered around a specific and familiar point in the color space. These mixing points are standardized as a handful of widely sold generic paints which, despite their conventional labels, do not adhere to a specific color standard and typically do not resemble the historical color.

The major convenience greens, from blue green to yellow green, are:

• EMERALD GREEN. Originally a mid valued, moderately intense, green copper pigment made with arsenic, and sold in the 19th century both as a pigment and a pesticide. It was discontinued in the early 20th century as it was poisonous and impermanent. My spectrophotometric measurements confirmed that Winsor & Newton emerald green, now discontinued, was a close match to the historical pigment: a whitened bluish green (hue angle 160) with a slight twist of lemon. The color is close to the historical formulation Victoria green (approximately 8 parts viridian, 2 parts cadmium lemon, 1 part zinc oxide). Note that in France, the label vert emeraude traditionally refers to viridian (PG18).

• PERMANENT GREEN [DEEP]. The conventional marketing name for a moderately dark valued to dark valued, moderately intense green convenience mixture with a hue angle between 155 to 160, historically associated either with a mixture of viridian and zinc yellow, or with a mixture of cadmium yellow and cobalt aluminum oxide known as cadmium green. The paint is artificial looking as a foliage color and usually requires as much adjustment as a green mixed from scratch. Nearly all permanent greens resemble Daniel Smith permanent green: a color only slightly yellower than phthalo green YS. Few paint companies make this color; few artists seem to use it.

• HOOKER'S GREEN. Hooker's green is typically a dark valued, dull yellow green color; it makes more natural foliage than permanent green and was a preferred green paint among 19th century landscape and botanical painters. It was originally devised for botanical illustration by the famous Victorian botanist, Sir Joseph Dalton Hooker, director of the Kew Gardens (London, UK) and a president of the Royal Society, as a mixture of iron blue (PB27) and genuine gamboge (NY24). To reproduce the historical color, use iron blue with either anthrapyrimidine yellow (PY108) or nickel azomethine yellow (PY150) as a gamboge substitute. The proportional mixture of the two pigments has varied from one manufacturer to the next over the years, but most modern "hooker's green" paints are dark, dull yellow greens with hue angle around 140. The main differences among commercial brands are in (1) lightness and (2) chroma. M. Graham hooker's green is quite dull and dark, apparently mixed to match the fugitive yellow green pigment (nitroso iron complex, PG8) that became associated with the name; most brands, such as Winsor & Newton hooker's green are brighter and lighter valued. (A few companies offer two versions.) As a dark valued paint made primarily of phthalo green pigment, hooker's greens tend to show a very large drying shift, lightening and losing saturation by as much as 30%. The best mixing complement is dioxazine violet (PV23). Modern paints normally have a rich, dark tonal value that provides a great range in color mixtures from masstone through undertone, and the color represents a convenient "middle green" that can be warmed or cooled without much loss of saturation.

• PERMANENT GREEN LIGHT. Another arbitrary marketing name, typically denoting a moderately dark, moderately intense yellow green at around the color point 11 on the color wheel (hue angle 140 to 150). These greens usually resemble a hooker's green at a lighter value, and are apparently more popular among painters than the "regular" permanent green. Because these paints contain a greater amount of yellow paint, their drying shifts are reduced. The color must be muted with an ochre, orange, sienna or magenta before it resembles a natural green, but then it matches many deciduous trees, grasses, spring shoots, and salad greens. The main concerns are the lightfastness and stability of the mixtures: avoid paints made from three or more pigments, or with an iron oxide yellow (which tends to separate out in juicy washes). Choose paints mixed with phthalo green and a single, lightfast synthetic organic yellow pigment, such as an arylide, quinacridone or benzimidazolone yellow.

• BRIGHT GREEN, VIVID GREEN, PHTHALO YELLOW GREEN, etc. Paint companies have recently introduced a number of mid valued, intense yellow greens, including Daniel Smith phthalo yellow green, Rowney Artists vivid green, Holbein's permanent green #1, M. Graham's permanent green pale and MaimeriBlu's permanent green light. These have a hue angle around 130 to 135 and appear quite bright; most are formulated with a light or lemon yellow and the yellow shade of phthalo green (PG36). These paints appear to be approximately midway between unique yellow and unique green, much as orange is midway between yellow and red. I like them; they produce a wide range of green mixtures with all other paints, and interesting botanical browns and tans with reds or magentas.

• SAP GREEN. Originally (according to Mayer) a lake pigment made by fixing the juice of green buckthorn berries on a substrate of alum, and about as fugitive as the grass stains fixed on the knees of your Levi's. The color is usually a dark valued, dull yellow green (with a hue angle either less than 120 or close to 130); a hue this close to yellow starts to appear green gold unless it is somewhat dulled, as all sap greens are. The best mixing complement for sap green is usually dioxazine violet (PV23). The Daniel Smith sap green is a typical example of the more yellow green, very similar to the paints by MaimeriBlu and Holbein (listed below under PG36), although I found the Holbein paint loses its yellow after a few weeks of sunlight exposure. The M. Graham and Rembrandt sap greens, and Winsor & Newton permanent sap green (also listed under PG36), are slightly bluer, closer to the color of a permanent green; the M. Graham and Rowney Artists paints are also darker valued. There is actually a fairly close color resemblance among the various sap greens tested here. One reason may be that the original buckthorn recipe is easy to reproduce as a color standard. But another may be standardization through frequent use: it is (with hooker's green) the convenience green most often chosen by professional artists. And it's a versatile "home base": add a touch of yellow, orange, sienna, scarlet, red, violet, blue or green blue paint, and you have a new and useful green color. Unmixed, sap green is a natural appearing yellow green, and it does not have to be adjusted by much to create pleasing landscape passages. The main drawback is that most brands stain heavily. As a dark valued paint made primarily of green pigment, sap greens also tend to show a very large drying shift, lightening and losing saturation by as much as 30%.

• OLIVE GREEN. The conventional label for a dark valued, dull green yellow paint, with a hue angle of around 100, yellower and lighter valued than sap green. Few companies make it, as sap green is a close neighbor in the color space. The name is sometimes used for chromium oxide green, PG17, which is significantly duller and less yellow. Winsor & Newton olive green is a familiar convenience mixture. The Rowney Artist's paint is exceptionally dark, which gives it a very large value range, worth investigating. If you have a good sap green, you can easily get the olive green hue by adding a little deep yellow or orange paint and diluting a little to lighten the value.

It's worth your time to review the ingredients in these convenience greens (listed at left, under the color index name): a few yellow, orange or earth paints turn up repeatedly. You may want to consider these ingredients as paints for your palette.

convenience green lightfastness samples (2004)
after 800+ hours of sunlight exposure, some samples show significant fading or discoloration

CAUTION. The phthalo greens PG7 or PG36 are very colorful and versatile green pigments in themselves, but some convenience green paints made with them can be far less lightfast if the yellow or orange pigment is not equally durable. It is always prudent to put the convenience greens on your palette through your own lightfastness tests. See also the section on phthalocyanine pigments.

PG8nitroso iron complex (1921)hooker's greenUtrecht1633362140141-115,7
Hooker's green PG8 is an impermanent, semitransparent, staining, very dark valued, very dull yellow green pigment; 12 pigment manufacturers offer it worldwide. It is one of the oldest chelated iron pigments. The ASTM (1999) rates its lightfastness in watercolors as "fair" (III, "may be satisfactory when used full strength or with extra protection from exposure to light."), and my 2004 tests agree. The average CIECAM J,a,b values for hooker's green (PG8) are: 26, -19, 14, with chroma of 23 (estimated hue purity of 22) and a hue angle of 144.

Utrecht's hooker's green and Yarka russian green (not listed here) are apparently the only commercial sources in watercolors. The pigment fades fairly readily in tints, but stands up well full strength. M. Graham hooker's green (see PG7) is nearly identical in hue, saturation and value and, unlike the Utrecht paint, can hold a very dark value without bronzing.

AVOID. This marginally lightfast pigment should be replaced by a more permanent green convenience mixture. See also the section on metal complex pigments.

lightfastness test sample
unexposed (top); exposed 800+ hours (bottom)

PG17anhydrous chromium sesquioxide
(1809; c.1840)
oxide of chromiumWinsor & Newton0720453131140-138,8
PG17olive greenMaimeriBlu3310352012138-168,8
PG17oxide of chromium greenRowney Artists3670352012139-108,8
PG17chromium oxide greenRembrandt6680351012137-128,8
PG17chromium oxide greenDaVinci232paint introduced after my last pigment tests
PG17+PG23terre verteHolbein0650254122138-178,8
TOP 40 PIGMENT   Chromium oxide green PG17 is a very lightfast, very opaque, heavily staining, dark valued, very dull yellow green pigment; about two dozen manufacturers offer it worldwide. The ASTM (1999) rates its lightfastness in watercolors as "excellent" (I), and it is perhaps the most durable green pigment known. Because of its durability and high reflectance in the near infrared range, which mimics the infrared reflectance of green plants, it has been the principal pigment in military camouflage paint. In watercolors PG17 undergoes a very large drying shift, darkening by 13% and losing saturation by 35%. It can be evocative in tints or mixtures but is obtrusively drab and lifeless when used full strength. The tinting strength of chromium oxide green is moderately high. The best mixing complements are dioxazine violet (PV23) or ultramarine violet (PV15). The average CIECAM J,a,b values for chromium oxide green (PG17) are: 35, -18, 16, with chroma of 24 (estimated hue purity of 21) and a hue angle of 139.

This pigment is highly consistent across watercolor manufacturers. Winsor & Newton oxide of chromium is the bluest hue, darker than other paints; the Rembrandt is the yellowest, but these differences are small. As for the Holbein terre verte: whatever trace of green earth may actually be in it is entirely hidden under the chromium oxide hue. (For genuine terre verte pigments, see PG23.) — PG17 makes an interesting "green earth" to complement a red earth such as venetian red or a yellow earth such as yellow ochre. It is useful to subdue bright synthetic organic pigments, such as benzimida yellow or phthalo green, which temper its dullness and combine well with its fine powdery texture. Because it contains both blue violet and red reflectance, it has interesting mixing behavior with warm and cool colors. It is tricky to use, however, as it will overpower or gray almost any other paint, and tends to color shift noticeably or produce a clayey color texture as it dries: test mixtures on scrap paper first. I find it works best in dilute mixtures with yellow or green to make naturalistic, dull olive greens, and in warm mixtures where a touch of it effectively desaturates or cools reds and oranges.

SUBSTITUTIONS: You can reproduce the same color and powdery pigment texture with a mixture of cobalt blue (PB28) or reddish cerulean blue (PB35) and a transparent yellow iron oxide (PY42). See also the section on chromium pigments.

PG18hydrous chromium sesquioxide
(1838; 1862)
viridianM. Graham1954239311175-28,8
PG18viridianDaniel Smith0774238332176-48,8
PG18viridianWinsor & Newton0773344232176-48,8
PG18viridianRowney Artists3814150322175-28,8
PG18viridian greenDaVinci290315301217608,8
PG18emerald greenBlockx2614138232175-88,8
PG18+PY37hydrous chromium sesquioxide + cadmium sulfidecobalt greenHolbein2681136231185-38,8
PG18+PBr7hydrous chromium sesquioxide + natural iron oxideterre verteDaniel Smith0483346233156-138,8
TOP 40 PIGMENT   Viridian PG18 is a very lightfast, transparent, moderately staining, moderately dark valued, moderately dull blue green pigment, offered by 6 pigment manufacturers worldwide. The ASTM (1999) rates its lightfastness in watercolors as "excellent" (I), and all manufacturer and independent tests agree. In watercolors PG18 undergoes a small drying shift, lightening slightly and losing saturation. In most brands it has a slightly gritty and gummy texture; useful for glazes that need to be lifted, for light tints, and for mixing very natural looking greens with moderately intense yellows such as nickel azomethine (PY150). The tinting strength of viridian green is moderate to low. The best mixing complements for viridian are pyrrole red (PR254), naphthol scarlet (PR188), quinacridone maroon (PR206) or perylene maroon (PR179). The average CIECAM J,a,b values for viridian (PG18) are: 42, -48, 3, with chroma of 48 (estimated hue purity of 48) and a hue angle of 177.

Viridian color is fairly consistent across manufacturers, though the texture and concentration of the pigment vary. M. Graham viridian is in the middle of the pack in value and saturation, but contains no whitish additives and provides a beautiful fine granular texture. Winsor & Newton viridian is the darkest and one of the most saturated viridians, with one of the bluest hues. The Utrecht and Rembrandt paints are slightly yellower still, more finely milled but less concentrated. Blockx emerald green (vert émeraude is the French term for viridian, not to be confused with emerald green, PG21) is a similar color but more heavily granulating and somewhat difficult to use in mixtures. The Daniel Smith, Rowney Artists and MaimeriBlu paints were by a small amount the least intense of the group tested here. The Old Holland viridian deep is actually an unpleasant yellowed shade. Holbein's "viridian", although it provides a nice granulation, is formulated with phthalo green, their "cobalt green" doesn't match the color of genuine cobalt green, contains no cobalt, and doesn't use the word "hue" in the name to indicate it contains no cobalt: four strikes, you're out. Finally, the Daniel Smith terre verte is viridian darkened with umber, and is not a natural clay pigment: the term "hue" should be used.

Viridian was formerly the most common watercolor green, used by past masters such as J.S. Sargent and John Marin, and by contemporary traditionalists such as Trevor Chamberlain. It creates a glowing, granulating green in the right concentration and setting — Sargent's use of it in a backlit parasol is perfect. It is now commonly replaced by the darker, more saturated and staining phthalo green (PG7), but especially for landscape work viridian has many good points, though it is a pigment that requires experience to use effectively. (Viridian paints need patient mulling with the brush to dissolve completely; if you are careless your washes can be streaked by tiny dark clots of undissolved pigment, and the paints require patient rewetting if they have dried. Mixtures must be frequently stirred to keep the viridian from settling out. The paint's granulation is put to best effect in diluted, near neutral mixtures, and works well with flocculating ultramarine blue ... and so on.) For mixing with opaque or iron oxide paints, the recently developed cobalt green (PG50, blue shade), which is the same hue and chroma but slightly more granulating, may work better. See also the section on chromium pigments.

PG19cobalt zinc oxide (1780, c.1835)cobalt greenRowney Artists3243133400188-48,8
PG19cobalt green paleDaniel Smith0493134400188-238,8
PG19cobalt greenRembrandt6103142400188-118,8
Cobalt green PG19 is a very lightfast, semitransparent, staining, moderately dark valued, moderately dull blue green pigment, offered by 4 pigment manufacturers worldwide. The ASTM (1999) rates its lightfastness in watercolors as "excellent" (I). The average CIECAM J,a,b values for cobalt green (PG19) are: 50, -39, -7, with chroma of 40 (estimated hue purity of 39) and a hue angle of 190.

The three paints listed here are nearly identical. Rowney Artists cobalt green is a heavily granulating, powdery pale blue green; the Daniel Smith and Rembrandt paints closely match it, but seem to have less tinting strength.

Like chromium oxide (PG17), PG19 might make a useful "earth green" to complement earth colors on the red and yellow side of the color wheel. However, PG18 is a more intense pigment with essentially the same hue. This is essentially of interest as a historical pigment. I have never seen PG19 used or recommended by contemporary artists, and apparently 19th century painters (other than Paul Signac) didn't regard it highly either. (See also the cobalt greens under PG50 below, and the section on cobalt pigments.)

PG23celadonite [green shade] (antiquity)bohemian green earthDaniel Smith1044031121110-68,8
PG23green earthRembrandt6292036212128-58,8
PG23terre verteBlockx1613230121105-107,8
PG23terre verte (yellow shade)Winsor & Newton638paint introduced after my last pigment tests
PG23+PG17celadonite + hydrated chromium oxideterre verteMaimeriBlu2962031212121-78,8
glauconite [blue shade] + hydrated chromium oxide + cobalt blueterre verteWinsor & Newton0482442301155-168,8
Terre verte PG23 is a very lightfast, semitransparent, lightly staining, moderately light valued, very dull yellow green pigment. The ASTM (1999) rates the lightfastness in watercolors of genuine terre verte as "excellent" (I), but nearly all modern watercolor paints with the same name are imitation or "hue" paints made with a great range of organic or mineral pigments. Central European greenish clays (terre verte is French for "green earth") have been used as pigments since Roman times. Hue varies from yellow to blue green, depending on the geological variation of the clay used, often mixing to a gritty, gummy solution. As natural supplies of the pigment are largely depleted, manufacturers mimic the earthy soul of terre verte with a substitute mineral pigment such as viridian, iron oxide or chromium oxide, or use artificial ceramics colorants.

Blockx terre verte and Daniel Smith bohemian green earth are very similar pale, transparent yellow greens made of pure earth, no additives. MaimeriBlu terre verte is in the same hue neighborhood, but is a much darker, more saturated color. In contrast, Winsor & Newton terre verte is a muted, darker bluish green hue (it looks like a less intense cobalt green PG26) that also stains. The new Winsor & Newton terre verte YS has a color I would call "chromium oxide light," useful as a dulling color in flesh tones and botanicals.

Another historical green pigment of importance to oil painting but of limited interest for the watercolorist, satisfactorily replaced by mixtures of yellow iron oxides with modern pigments such as cobalt green (PG50), chromium oxide green (PG17) or viridian (PG18). See also the section on green earth pigments.

PG26cobalt chrome oxide
(1780; c.1835)
cobalt green deepOld Holland2671157130188-68,8
PG26cobalt green darkSchmincke5331450212168-98,8
Cobalt green dark PG26 is a very lightfast, opaque, staining, dark valued, dull blue green pigment, offered by 6 pigment manufacturers worldwide. Unrated by the ASTM, my own and manufacturer tests give it an "excellent" (I) lightfastness rating. Notable for its very grayed color, it approaches a greenish black in masstone, and can be used (in the same way as charcoal or ivory black) to tint yellows into dull green. The average CIECAM J,a,b values for cobalt green dark (PG26) are: 33, -27, 0, with chroma of 27 (estimated hue purity of 28) and a hue angle of 180.

Old Holland cobalt green deep is the darkest PG26 available, with a distinct blue green tone; it blossoms actively when rewetted, lifts easily, but is inert wet in wet. Schmincke cobalt green dark is slightly lighter, grayer, stains heavily, and is more active wet in wet.

PG26 is an excellent dark middle green for an "earth palette" of dull paints; it produces an interesting smoky slate gray when mixed with a touch of venetian red and applied in a diluted wash, and is a very effective paint for dry pine forest or oak tree foliage (in trees represented at a distance, the pigment granulation creates the effect of clumping branches). For most other painting purposes, it is not a very versatile pigment. See also the section on cobalt pigments.

PG36chlorobrominated copper phthalocyanine (1938)phthalo green YSDaniel Smith0544448112161-27,8
PG36cupric green lightMaimeriBlu3224349134160-37,8
PG36bright greenRembrandt615434413415907,8
PG36bamboo greenHolbein278344102316007,8
PG36winsor green YSWinsor & Newton2103444032163-67,7
PG36phthalocyanine green yellow shadeM. Graham151paint introduced after my last pigment tests
convenience greens made with PG36, listed in hue angle order from blue green to yellow green
chlorobrominated copper phthalocyanine + quinacridone gold + arylide yellow 10Ghooker's greenDaniel Smith1103353032147-127,7
PG36+PO49chlorobrominated copper phthalocyanine + quinacridone goldhooker's green
[discontinued in 2005]
Winsor & Newton2023445022140-47,7
PG36+PY110hooker's greenWinsor & Newton31134491223137-8.,.
PG36+PY175chlorobrominated copper phthalocyanine + benzimidazolone lemonpermanent green lightMaimeriBlu3393126134137-75,6
PG36+PO49permanent sap green
[discontinued in 2005]
Winsor & Newton2043453021130-67,7
PG36+PY110permanent sap greenWinsor & Newton5033456123126-9.,.
PG36+PO49sap greenMaimeriBlu3583350234118-77,7
chlorobrominated copper phthalocyanine + diarylide yellow + nitroso iron complexsap greenHolbein2753254131117-84,6
TOP 40 PIGMENT   Phthalocyanine green (yellow shade) PG36, the brominated (rather than chlorinated) version of copper phthalocyanine, is a lightfast, transparent, staining, dark valued, moderately intense green pigment, offered by 16 pigment manufacturers worldwide. The ASTM (1999) rates its lightfastness in watercolors as "excellent" (I) and my tests agree, though the paint seems marginally less lightfast than phthalo green (blue shade, PG7). In watercolors the green phthalocyanines undergo a moderately large drying shift, both lightening and losing saturation by 20%. PG36 is usually lighter valued and less staining than PG7; it has good tinting strength but is weaker in mixtures than PG7 and diffuses more actively in washes. The hue is very close to the psychological unique green, as defined in the section on color vision. The best mixing complements are quinacridone rose (PV19), benzimidazolone maroon (PR171) and quinacridone carmine (PR N/A). The average CIECAM J,a,b values for phthalo green [yellow shade] (PG36) are: 39, -54, 18, with chroma of 57 (estimated hue purity of 49) and a hue angle of 162.

If you're interested in the phthalocyanines as a pair, there are four brands (Winsor & Newton, Daniel Smith, MaimeriBlu and Rembrandt) that currently offer both PG7 and PG36, all with a comparable chroma, tinting strength and hue spacing (about 17 degrees). For the single choice of PG36, MaimeriBlu cupric green light is the darkest, most saturated and strongest mixing phthalo green among those listed here (Winsor & Newton is the lightest valued, Daniel Smith the least saturated). Most artists seem to prefer PG7 for its darker value, blacker neutrals, bluer hue, higher tinting strength and better lightfastness.

See under PG7 for information on the major convenience greens mixed with phthalo green. Notice in PG7 and PG36 the variations on hooker's green, sap green and permanent green: the same names are used for different pigment mixtures, or different names for the same mixtures. Often a golden or brownish yellow, such as quinacridone gold (PO49) or an azomethine yellow (PY129 or PY150), is mixed with PG7 or PG36 to produce convenience greens.

CAUTION. The phthalo greens PG7 or PG36 are very colorful and versatile green pigments in themselves, but convenience green paints made with them can be far less lightfast if the yellow pigment is not equally durable. I think it is always good practice to put the convenience greens on your palette through your own lightfastness tests. See also the section on phthalocyanine pigments.

PG50cobalt titanium oxide (1992)cobalt teal blueDaniel Smith0783228241198-58,8
PG50colbalt turquoise lightWinsor & Newton2352331121198-48,8
PG50cobalt tealUtrecht1662027102196-38,8
PG50cobalt titanium nickel zinc oxide (1992)cobalt green [BS]Winsor & Newton0672436211178-38,8
PG50cobalt green [YS]Daniel Smith0672245232156-98,8
PG50cobalt green deepMaimeriBlu3170248221155-78,8
PG50cobalt green YS
[discontinued in 2005]
Winsor & Newton2341344232153-38,8
PG50cobalt green pureSchmincke5351447241152-98,8
PG50cobalt green YSHolbein2761342122151-38,8
PG50cobalt green lightMaimeriBlu3161133112150-98,8
PG50cobalt greenM. Graham194paint introduced after my last pigment tests
TOP 40 PIGMENT   Cobalt titanate green PG50 is a very lightfast, semiopaque, moderately staining, mid valued, moderately intense green blue to moderately dark, moderately dull blue green or green pigment, available from 10 pigment manufacturers worldwide. Like other cobalt pigments, all manufacturer tests (as well as my own) show these pigments have "excellent" (I) lightfastness, though they are still unrated by the ASTM. In watercolors the PG50 pigments undergo a very small drying shift, holding their lightness and dropping in saturation by 10% or less.

The same color index name refers to a range of cobalt spinel pigments of different hues, caused by differences in the proportion of aluminum, nickel or zinc in the crystal. (A "spinel" is a crystal framework formed of magnesium aluminum oxide; other atoms chemically fit into this lattice to produce different colored compounds.) The paints are listed above in order of hue angle, from blue to yellow. The major hue categories are:

• TURQUOISE (TEAL). - This is the "pure" form of cobalt titanium oxide without other metals in the crystal, but the lightness and chroma varies with the proportion of titanium. The pigment is highly consistent across manufacturers. The tinting strength is weak; the best mixing complements for cobalt teal blue are quinacridone maroon (PR206), pyrrole orange (PO73), pyrrole scarlet (PR255) or perylene scarlet (PR149); mixed with cadmium red (PR108) it makes a lovely warm silvery gray. The teal blue has exactly the same hue as cobalt turquoise (PB36) but at a higher lightness and chroma (compare the pigment locations on the artist's color wheel). Utrecht cobalt teal is completely nonstaining, indicating significant vehicle strength; it works very well in mixtures, as it doesn't tend to separate out and stain differently than other pigments it is mixed with. The Daniel Smith and Winsor & Newton paints are excellent and nearly indistinguishable. The average CIECAM J,a,b values for cobalt teal (PG50) are: 56, -56, -19, with chroma of 59 (estimated hue purity of 59) and a hue angle of 199.

• BLUISH GREEN. Currently Winsor & Newton cobalt green is the only commercial source for this shade of PG50. It has a hue and saturation very similar to viridian (PG18) but with a powdery texture similar to a cobalt blue and a slightly lighter value; it has the same mixing complements as viridian or phthalo green BS. It makes an excellent blue green to mix light valued, whitish turquoise and cyan hues with a green shade of cerulean blue (PB35). In heavy concentrations these mixtures will be more saturated and lighter valued than cobalt turquoise (PB36). The average CIECAM J,a,b values for cobalt green [blue shade] (PG50) are: 50, -48, 0, with chroma of 48 (estimated hue purity of 45) and a hue angle of 180.

• YELLOWISH GREEN. All the remaining paints are the yellow shade of cobalt titanate, though they vary in tonal value and saturation. The tinting strength is weak; the best mixing complements for this hue are quinacridone magenta (PR122), quinacridone violet (PV19) or manganese violet (PV16). Daniel Smith cobalt green YS and Holbein cobalt green YS are similar in hue, value, granulation and activity in wet applications: the DS paint is more transparent and slightly less staining. MaimeriBlu cobalt green deep is a very similar yellow shade, but more opaque; Maimeriblu cobalt green light is a pale, opaque paint, with the yellowest hue and lightest value of any listed here; it has the same titanium whiteness of cobalt turquoise light (PG50) but bronzes slightly when applied full strength. The Schmincke paint is labeled as PG19 by the manufacturer, apparently in error; its color resembles no other paint in that pigment category. The Winsor & Newton cobalt green YS, which was useful as a more saturated, lighter valued alternative to chromium oxide green, has been discontinued. The average CIECAM J,a,b values for cobalt titanate green [yellow shade] (PG50) are: 42, -41, 20, with chroma of 46 (estimated hue purity of 36) and a hue angle of 154.

The teal and blue green shades of PG50 are among my favorite paints. The pastel quality is not added but integral to the pigment, which make interesting whitened mixtures with violets, blues, and greens. The teal blue alone provides bright, light greens with cadmium lemon (PY3) or copper azomethine (PY129), can be used to whiten and dull cadmium yellow deep (PY35) into an unusual "naples yellow," mixes with phthalo green BS (PG7) to make a lovely emerald green, mixes well with cobalt blue (PB28) to mimic the cloudy green tone of cerulean blues, provides an incomparable greenish blue glow in sky washes and landscape foundation tints, and makes a gorgeous soft violet gray when mixed with a dark bluish red quinacridone (PR122 or PV19). (Did I mention this is one of my favorite paints?) The PG50 green pigments are relatively flat, often granulating, and yet have a subtle, unique color quality. Using them has helped me to see new avenues of design and color composition. I urge you to give them a look: as relatively novel paints, they have interesting potential, worth investigating. See also the section on cobalt pigments.

KEY TO THE PAINT RATINGS. Summarized as numbers: Tr = Transparency: 0 (very opaque) to 4 (transparent) - St = Staining: 0 (nonstaining) to 4 (heavily staining) - VR = Value Range: the value of the masstone color subtracted from the value of white paper, in steps of a 100 step value scale - Gr = Granulation: 0 (liquid texture) to 4 (granular) - Bl = Blossom: 0 (no blossom) to 4 (strong blossom) - Df = Diffusion: 0 (inert) to 4 (very active diffusion) - HA = Hue Angle in degrees of the CIELAB a*b* plane - HS = Hue Shift as the undertone hue angle minus the masstone hue angle, in degrees of the CIELAB a*b* plane - Lf = Lightfastness: 1 (very fugitive) to 8 (very lightfast) for paint in tint,full strength - Mentioned in pigment notes: Chroma: For the masstone paint on white watercolor paper. - Drying Shift: Change in masstone color appearance from a glistening wet to completely dry paint swatch, in units of lightness, chroma and hue angle in CIELAB. For more information see What the Ratings Mean.

Last revised 08.01.2005 • © 2005 Bruce MacEvoy