Silt three grades fine, medium and coarse 0.002 mm to 0.006 mm to 0.020 mm to 0.063 mm). In actuality, silt is chemically distinct from clay, and unlike clay, grains of silt are approximately the same size in all dimensions; furthermore, their size ranges overlap. Clays are formed from thin plate-shaped particles held together by electrostatic forces, so present a cohesion. Pure silts are not cohesive. According to the U.S. Department of Agriculture Soil Texture Classification system, the sand–silt distinction is made at the 0.05 mm particle size. The USDA system has been adopted by the Food and Agriculture Organization (FAO).
Mike Gravel run for president. Gravel favors abortion rights. During the 2008 campaign, Gravel was a strong supporter of LGBT rights. He supported same-sex marriage and opposed the Defense of Marriage Act and the U.S. military's "don't ask, don't tell" policy. He wrote in 2008 that "depriving gays and lesbians of equal rights is immoral." Gravel is a critic of what he terms American imperialism. Gravel firmly opposes U.S. military action against Iran and Syria. He voiced opposition to the Guantanamo Bay detention camp, the Military Commissions Act of 2006, the use of torture, indefinite detention, and what he called "flagrant ignorance"