Mineral oil, cosmetic grade. Treatment of constipation and colic in Animals. Safe to be used by humans for constipation. Liquid paraffin, also known as paraffinum liquidum or Russian mineral oil , is a very highly refined mineral oil used in cosmetics and medicine. Cosmetic or medicinal liquid paraffin should not be confused with the paraffin used as a fuel. It is a transparent, colourless, nearly odourless, and oily liquid that is composed of saturated hydrocarbons derived from petroleum.