Chromium is a steel-gray metallic element naturally found in rocks, soil, animals, and in volcanic dust and gases. It has three main forms -- chromium (0), chromium (III) and chromium (VI), the last two being the most important. In very small amounts, chromium (III) is an essential nutrient in our diet. It is believed to help insulin maintain normal glucose and cholesterol levels, and enhance fat metabolism. Both chromium (III) and (VI) are used for making steel and other alloys, bricks in furnaces, dyes and pigments, for chrome plating, leather tanning, and wood preserving.