Acid stained concrete is being used in both commercial and residential applications to create unique custom floors. Acid penetrates the concrete surface reacting chemically with the components to produce a finish much like polished marble. This is an affordable way to give a concrete floor the rich appearance of marble at a fraction of the cost. The base ingredient is hydrochloric acid which will call for the use of safety precautions and good ventilation when working. You can use this treatment to give you a number of transparent colors but only a limited range of shades. However you could still find shades from dark earth tones through to vibrant blue–greens. Solid color stains are your next option which acts both as a transparent colorant and a sealant. Solid color stains can produce a brighter hue than a concrete acid stain.