Michael Harding Artists Watercolor - Moss Green, 15 ml

Pigment Information

This color contains the following pigments:

PY150-Nickel Azo Yellow

PB29-Ultramarine [Blue]

PR209-Quinacridone Red

Pigment Name

PY150-Nickel Azo Yellow

Pigment Type

inorganic

Chemical Name

nickel azomethine yellow

Chemical Formula

C30H18Cl2N6NiO4

Properties

Nickel Azo Yellow is a transparent, moderately staining yellow pigment with high tinting strength. It is considered a good color match in botanical and landscape painting for natural gamboge (NY24), a historic yellow pigment with fair to poor lightfastness.

Permanence

Nickel azomethine yellow has excellent lightfastness.

Toxicity

Nickel azo yellow pigment is mildly toxic, and is often labeled as hazardous. Avoid respiratory and skin exposure to pigment dust. It should be disposed of properly with other hazardous wastes, not washed down the sink.

History

Nickel azomethine yellow has been developed as an artist pigment becasue it is a close match for gamboge, a historic yellow.

Pigment Name

PB29-Ultramarine [Blue]

Pigment Type

inorganic

Chemical Name

complex silicate of sodium and aluminum with sulfur

Chemical Formula

Na8-10Al6Si6O24S2-4 or Na6-8Al6Si6O24S2-4

Properties

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.

Permanence

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.

Toxicity

Ultramarine has no significant hazards.

History

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.

Pigment Name

PR209-Quinacridone Red

Pigment Type

organic, quinacridone

Properties

Quinacridone Red is a bright, clean red pigment with average drying time. Quinacridone pigments have relatively low tinting strength in general. For this reason, quinacridone colors are often expensive, because more pigment is required in the formulation.

Permanence

Quinacridone Red has excellent permanence and lightfastness.

Toxicity

Quinacridone Red has no known acute hazards. Overexposure to quinacridone pigments may cause skin irritation. Quinicridone pigments contain a compound found to be a skin, eye, and respiratory irritant.

History

Although quinacridone compounds became known in the late 19th century, methods of manufacturing so as to make them practical for use as commercial pigments did not begin until the 1950s. Quinacridone pigments were first developed as coatings for the automotive industry, but were quickly adopted by artists.