Oil paint
Oil paint is the traditional medium for impasto painting, due to its thick consistency and slow drying time. Acrylic paint can also be used for impasto by adding heavy body acrylic gels. Impasto is generally not seen done in watercolor or tempera without the addition of thickening agent due to the inherent thinness of these media. An artist working in pastels can produce a limited impasto effect by pressing a soft pastel firmly against the paper.