Ultramarine Blue (Green Shade) Pigment
The greenest shade of ultramarine blue we could find, a synthetic inorganic blue pigment consisting of a double silicate of aluminum and sodium with sulfide and occurs in nature as a component of the semi-precious stone, lapis lazuli.
Ultramarine Blue (Green Shade)
Pigment Names | |||||||
Common Names (rock): | Dutch: ultramarijnblauw English: ultramarine blue French: bleu outremer German: Ultramarinblau Italian: blu oltremare Spanish: azul ultramarino | ||||||
Alternate Names: | azure blue, azzurrum ultramarine, azzurrum transmarinum, azzuro oltramarino, azur d'Acre, Lazurstein, pierre d'azur | ||||||
Nomenclature: |
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Origin and History
In 1814, Tassaert observed the spontaneous formation of a blue compound, very similar to ultramarine, if not identical to it, in a lime kiln at St. Gobain, which caused the Societé pour l'Encouragement d'Industrie to offer, in 1824, a prize for the artificial production of the color. Processes to make the artificial pigment were devised by Jean Baptiste Guimet (1826) and Christian Gmelin (1828). Still, while Guimet kept his process a secret, Gmelin published his and thus became the founder of the "artificial ultramarine" industry.
Source
Ultramarine is a blue pigment consisting of a double silicate of aluminum and sodium with sulfide, occurring in nature as a component of lapis lazuli. The Colour Index designation is Pigment Blue 29, and the Colour Index number is 77007. Ultramarine is one of the most complex mineral pigments, a sulfur-containing compound of sodium-silicate, essentially a mineralized limestone containing a blue cubic mineral called lazurite (the major component of lapis lazuli). The term ultramarine designates both the natural mineral and the artificial pigment, although today, most distinguish the natural mineral by its name, lazurite, or the rock containing it, lapis lazuli.
Permanence and Compatibility
Ultramarine is a synthetic blue pigment rated by the American Society of Testing and Materials (ASTM International) as lightfastness category I, which is the highest lightfastness. It is compatible with all pigments but is sensitive to weak acids, so avoid using it with acidic mediums and supports and in outdoor applications where it may be exposed to acid air pollution and rain.
Oil Absorption and Grinding
Ultramarine blue absorbs a moderate amount of oil (38 to 42 grams of linseed oil per 100 grams of pigment), which may slow the drying of oil paint. Hence, it is a moderate-drying oil color. It is a highly refractive pigment and is difficult to grind in oil because of its poor wetting properties, although it easily disperses in water.
Toxicity
Ultramarine blue is not considered toxic, but care should be taken when handling the dry powder pigment to avoid inhaling the dust. This is an FDA-compliant product recommended for food-contact products in Northern America. The pigment complies with the purity requirements in 21 CFR 73.2725.
For more information on handling pigments safely, please visit How to Safely Handle Art Materials and Pigments.
Pigment Information | |
Color: | Blue |
Pigment Classification: | Synthetic Inorganic |
Colour Index: | Pigment Blue 29 (77007) |
Chemical Name: | Sodium Calcium Aluminum Silicate Sulfate |
Chemical Formula: | (Na, Ca)8Al6Si6O24(S, SO4) |
CAS No.: | 57455-37-5 |
Series No.: | 3 |
FDA Approved: | Section 178-3297 |
ASTM Lightfastness | |
Acrylic: | I |
Oil: | I |
Watercolor: | I |
Physical Properties | |
Particle Size (mean): | 1.8 microns |
Density: | 2.35 g/cm3 |
Hardness: | 5.0–5.6 |
Refractive Index: | 1.50–1.55 |
Tap Density: | 0.50–8.0 g/cm2 |
Free Sulfur: | 200 ppm |
Oil Absorption: | 38–42 grams oil / 100 grams pigment |
Health and Safety | No acute or known chronic health hazards are associated with this product's anticipated use (most chemicals are not thoroughly tested for chronic toxicity). Protect yourself against potentially unknown chronic hazards of this and other chemical products by keeping them out of your body. Do this by avoiding ingestion, excessive skin contact, and inhaling spraying mists, sanding dust, and vapors from heating. Conforms to ASTM D-4236. |
For a detailed explanation of the terms in the table above, please visit Composition and Permanence.
SKU | 417-18 |
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Brand | Rublev Colours |
Vendor | Rublev Colours |
Processing Time | Usually ships the next business day. |
Color | Blue |
Pigment Type | Inorganic, Synthetic |