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
The Plastic People of the Universe Pact troops invaded Czechoslovakia. This led to the overthrow of Dubček and to what came to be known as the normalization process. Less than a month after the invasion, Plastic People of the Universe was formed. Bassist Milan Hlavsa formed the band in 1968 and was heavily influenced by Frank Zappa and the Velvet Underground (Zappa's band, the Mothers of Invention, had a song called "Plastic People" from their 1967 album "Absolutely Free"). Czech art historian and cultural critic Ivan Jirous became their manager/artistic director in the following year, fulfilling a role similar to the one Andy Warhol had with