Oil paint considered drying, those with an iodine number of 115-130 are semi-drying, and those with an iodine number of less than 115 are non-drying. Linseed oil, the most prevalent vehicle for artists' oil paints, is a drying oil. When exposed to air, oils do not undergo the same evaporative process that water does. Instead, they polymerize into a dry semisolid. This rate of process can be very slow, depending on the oil. The advantage of the slow-drying quality of oil paint is that an artist can develop a painting gradually. Earlier media such as egg tempera dried quickly, which prevented the
World oil market chronology from 2003 two major oil suppliers reducing supply generated fears of a repeat of the 1973 oil crisis. The mid-July decision of Saudi Arabia to increase oil output caused little significant influence on prices. According to the oil minister of the Islamic Republic of Iran, Gholam-Hossein Nozari, the world markets were saturated and a Saudi promise of increased production would not lower prices. Several Asian refineries were refusing Saudi petroleum in late June because they were over priced grade. On July 3, "the Brent North Sea crude contract for August delivery rose to $US145.01 a barrel" in Asian trade. London Brent crude