Brickform E-Stains are eco-friendly, penetrating, reactive stains that produce unique color effects in finished cementitious surfaces. The product creates an acid-like chemical reaction within the concrete substrate that slightly etches the concrete surface without harmful acid effects. Reduce the color value by blending the stain with E-Stain Plus. Produce special colors by blending two or more colors together. Solomon Colors. 800-624-0261.