The formulation of each color is modified individually to compensate for the inherent differences in the working characteristics of pigments. The result is an even consistency across the entire palette of colors.
Color Swatch created using heavy application/medium application/50% tint and was applied on acrylic primed canvas (7 oz) material.
ferric ammonium ferrocyanide
Antwerp Blue is a slightly warm and less saturated blue with good transparency and undertone clarity. It is a pale variety of Prussian Blue with 75% inert pigment. It has similar properties to pure Prussian Blue, but its overall performance is inferior.
Antwerp Blue can fluctuate, fading in the light and recovering in the dark. In watercolor form, it fades when mixed with white pigment or extender. Although it has reasonably good lightfastness and permanence, it is not considered ideal for permanent painting.
Antwerp Blue is mildly toxic by ingestion, but is considered safe for external use. In the United States, ferric ferrocyanide is permitted as a coloring ingredient for externally applied cosmetics, but not for lipsticks or internal use. If the pigment is exposed to ultraviolet radiation, heated, or treated with acid, it becomes reactive and releases toxic hydrogen gas.
There has been some confusion and controversy about whether ferric ferrocyanide and ferric ammonium ferrocyanide should be classified as a "cyanide" and as a toxic or environmental pollutant. The United States Environmental Protection Agency has issued an administrative ruling that ferric ferrocyanide is not a toxic pollutant, and that its use as an ingredient in road salt and deicing mixes is permitted.
Antwerp Blue was developed through experimentation with Prussian Blue.
Haarlem Blue, Mansa Blue, Mineral Blue
complex silicate of sodium and aluminum with sulfur
Na8-10Al6Si6O24S2-4 or Na6-8Al6Si6O24S2-4
Ultramarine is the standard warm blue, a brilliant blue pigment that has the most purple and least green in its undertone. It has a moderate to high tinting strength and a beautiful transparency. Synthetic Ultramarine is not as vivid a blue as natural Ultramarine. Ultramarine dries slowly in oil and tends to produce clean, though granular, washes in watercolor. French Ultramarine mixes well with Alizarin colors in oil and watercolor form to create a range of purples and violets. It can dull when mixed with white in acrylic form, but mixes well with other colors. The shade varies based on manufacturer. Considered a great color for glazes, it is not suitable for frescoing.
Ultramarine has excellent permanence, although synthetic Ultramarine is not as permanent as natural Ultramarine. It may discolor if exposed to acid because of its sulfuric content.
Ultramarine has no significant hazards.
The name for this pigment comes from the Middle Latin ultra, meaning beyond, and mare, meaning sea, because it was imported from Asia to Europe by sea. It is a prominent component of lapis lazuli and was used on Asian temples starting in the 6th century. It was one of the most expensive pigments in 16th century Europe, worth twice its weight in gold, and so was used sparingly and when commissions were larger. Ultramarine is currently imitated by a process invented in France in 1826 by Jean Baptiste Guimet, making blue affordable to artists and extending the range of colors on their palettes.
Artificial Ultramarine, French Blue, French Ultramarine, Gmelin's Blue, Guimet’s Blue, Permanent Blue, Royal Blue, Synthetic Ultramarine. New Blue describes particular shades of Ultramarine. Armenian Blue and Lazuline Blue are names for genuine Lapiz Ultramarine. Sky Blue is a pale tone of Ultramarine.
® Holbein is a registered trademark.