Concrete acid stain is true to new or old, plain or colored concrete surfaces. These come in 10 basic colors. Even though they are often called acid stains, acid isn't the ingredient that colors the concrete. Metallic salts in an acidic, water based solution interact with the concrete to permanently colour of the surface. Siliceous aggregates such as gravel or sand, usually do not react with the stain. Surfaces containing a better content of cement will react more than one with less cement yielding more intense colors. _stained_concrete_
Since each surface differs from the others, results may vary in one surface to another. We always recommend testing a tiny area to determine how a final result will appear. Remember that the final color are not apparent until the sealer may be applied. With wood stain you'll probably still see the grain from the wood through the stain, acid stain is quite similar to wood stain as you can see all defects or finishing marks through it.
Factors that will affect the final results include:
Cement properties and amount used, Admixtures and sort of aggregate used.
Concrete finishing methods, concrete age, and moisture content
Porosity and Texture from the surface
Weather conditions when the stain is applied