Ruby other rubies of similar quality. After color follows clarity: similar to diamonds, a clear stone will command a premium, but a ruby without any needle-like rutile inclusions may indicate that the stone has been treated. Ruby is the traditional birthstone for July and is usually more pink than garnet, although some rhodolite garnets have a similar pinkish hue to most rubies. The world's most valuable ruby is the Sunrise Ruby. Rubies have a hardness of 9.0 on the Mohs scale of mineral hardness. Among the natural gems only moissanite and diamond are harder, with diamond having a Mohs hardness of
Birthstone American Gem Trade Association and Jewelers of America added spinel as an additional birthstone for August. Britain's National Association of Goldsmiths created their own standardized list of birthstones in 1937. Eastern cultures recognize a similar range of gemstones associated with birth, though rather than associating a gem with a birth month, gemstones are associated with celestial bodies, and astrology is employed to determine the gemstones most closely associated with and beneficial to a particular individual. For example, in Hinduism there are nine gemstones associated with the "Navagraha" (celestial forces including the planets, the sun, and the moon), known in Sanskrit