The color Persian blue is named from the blue color of some Persian pottery and the color of tiles used in and on mosques and palaces in Iran and in other places in the Middle East. Persian blue is a representation of the color of the mineral lapis lazuli which comes from Persia and Afghanistan. The color azure is also named after the mineral lapis lazuli.
The first recorded use of Persian blue as a color name in English was in 1669.1
The medium tone of Persian blue shown at right is the color called Persian blue in color sample #178 of the ISCC-NBS color list.
The color Persian indigo is displayed at right. Another name for this color is regimental because in the 19th century it was commonly used by many nations for navy uniforms, though it is seldom used in modern times.
Persian indigo is named for an association with a product from Persia: Persian cloth dyed with indigo.
The first recorded use of regimental (the original name for the color now called Persian indigo) as a color name in English was in 1912.2
Architecture
Military
New Age Metaphysics
Persian carpets
Maerz and Paul A Dictionary of Color New York:1930 McGraw-Hill Page 201; color sample of Persian blue: Page 95 Plate 36 Color Sample L4 ↩
Maerz and Paul A Dictionary of Color New York:1930 McGraw-Hill Page 203 (It is also stated under the entry on Persian Blue on page 201 that the color on Plate 47 Color Sample C10 (regimental) is a [darker] tone of Persian Blue.); color sample of Regimental: Page 117 Plate 47 Color Sample C10 ↩
Picture of the Interior of the Shah Mosque: /wiki/File:Shah_mosque2.jpg ↩