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Blue has been an important colour in art and decoration since ancient times. The semi-precious stone lapis lazuli was used in ancient Egypt for jewellery and ornament and later, in the Renaissance, to make the pigment ultramarine, the most expensive of all pigments. [3]
Blue pigments are natural or synthetic materials, traditionally made from minerals, Being water-insoluble by definition, blue pigments used to make the blue colors in inks and paints. Some major blue pigments are indigo, Prussian blue, and copper phthalocyanine. Historically lapis lazuli was important.
A campfire burning with blue and green flame colorants Different colors of natural flame from a bunsen burner, without additives. Colored fire is a common pyrotechnic effect used in stage productions, fireworks and by fire performers the world over.
This can only be used as a very rough guide, for instance if a narrow range of wavelengths within the band 647–700 nm is absorbed, then the blue and green receptors will be fully stimulated, making cyan, and the red receptor will be partially stimulated, diluting the cyan to a greyish hue.
The second method was known as 'China blue' due to its resemblance to Chinese blue-and-white porcelain. Instead of using an indigo solution directly, the process involved printing the insoluble form of indigo onto the fabric. The indigo was then reduced in a sequence of baths of iron(II) sulfate, with air oxidation between each immersion. The ...
Blue glazed faience ornaments have been found to have been produced during 4th millennium Indus Valley civilization (present day India and Pakistan). [10] In Iran and Mesopotamia, it was used to make jewellery and vessels. In Egypt, it was used for the eyebrows on the funeral mask of King Tutankhamun (1341–1323 BC). [11]
In borosilicate glasses rich in boron, sulfur imparts a blue color. With calcium it yields a deep yellow color. [4] Manganese can be added in small amounts to remove the green tint given by iron, or in higher concentrations to give glass an amethyst color. Manganese is one of the oldest glass additives, and purple manganese glass was used since ...
Cobalt blue is a commonly used color for interior decorating. [7] Automobiles. Several car manufacturers including Jeep and Bugatti have cobalt blue as paint options. Construction. Because of its chemical stability in the presence of alkali, cobalt blue is used as a pigment in blue concrete. Sports