PRODUCT IDENTIFICATION

57455-37-5, 67053-79-6

309-928-3, 235-811-0, 215-111-1

Na₂OSAl₂O₃SiO₂

CLASSIFICATION

Inorganic pigment

EXTRA NOTES

PHYSICAL AND CHEMICAL PROPERTIES

dark blue powder

>1000 C (Decomposes)

Insoluble

REFRACTIVE INDEX

GENERAL DESCRIPTION & EXTERNAL LINKS

Members of pigment blue

Wikipedia Linking:http://en.wikipedia.org/wiki/Ultramarine

http://www.webexhibits.org/
Brief description of Ultramarine:The finest blue known to the ancients, was obtained from the precious stone lapis lazuli (lazurite), a costly mineral. The mineral lazurite is a complex sodium calcium aluminum silicate sulfate. Lapis lazuli has been mined for centuries from a location still in use today in the mountain valley of Kokcha, Afghanistan. First mined 6,000 years ago, the rock was transported to Egypt and later to Europe where it was used in jewelry and paint pigment. Europeans called the expensive powdered pigment ultramarine, which literally means over the sea. Since the 19th century, ultramarine has been manufactured artificially

http://www.ut.ee
The natural variety is a very costly blue pigment with exceptional chemical stability except in the presence of acids. It is two types of ultramarine blue:  natural ultramarine and synthetic ultramarine. Natural Ultramarine  is famous for having been the most expensive pigment. It was more expensive than gold during the Renaissance. First used in 6th century Afghanistan, the pigment found its most extensive use in 14th and 15th century illuminated manuscripts and Italian panel paintings, often reserved for the cloaks of Christ and the Virgin. Genuine blue pigment is from the semi-precious stone, lapis lazuli, which is a mixture of the blue mineral, lazurite, with calcspar and iron pyrites. Natural ultramarine is unaffected by red heat or by alkalis but is decomposed by dilute acids, even acetic acid, with complete loss of color and the discharge of hydrogen sulphide gas. The blue is stable, however, in strong light and many specimens which are several hundred years old show no apparent change in color. Synthetic ultramarine is one of the best-documented pigments of the nineteenth century probably because its invention was requested of chemists and not the result of their independent research. Ultramarine, genuine made from the semi-precious gem lapis lazuli was so costly in the nineteenth century that artists infrequently used it. The hue is a necessary component in a balanced palette of warm and cool colors; without it a cool, deep blue is lacking. In chemical composition and structure it is identical with the natural ultramarine. This blue is stable under all conditions, except in the present of acids. It is permanent to light and is unaffected by high temperatures. Since it is unaffected by alkalis, it is stable in fresco. Synthetic ultramarine is today quite widely used as an artist´s pigment and is known to many as "French ultramarine" because of its discovery (1830) and long production in France.

http://cabinetmagazine.org/
EARLY 13TH CENTURY: Ultramarine, which contains more impurities than blue particles, is still the most difficult artist's pigment to grind by hand. Some improvements in its production make manufacturing more efficient—meaning more reliable supplies for artists who are using the color to portray queens, kings, and religious figures. But this also increases demand for lapis lazuli gems. As its price surpasses that of gold, ultramarine blue literally becomes the material wealth it had heretofore signified. Patrons commonly specify in writing the exact amount of ultramarine blue they will purchase for the artist to use in commissioned paintings.

APPEARANCE

dark blue powder

OTHER INFORMATION