Textures and exposures provide a tactilely and/or visually different surface effect. Depth can vary to expose a little or a lot of the stone used in the mix.
Form Finished: The stone, surrounded completely by the cement and sand matrix, is not visible. Color tends to be uneven or mottled. If this is unacceptable, etched, blasted, retarded, or polished finishes must be selected.
Acid Etched: Acid etching uses a high-pressure sprayed acidic water wash to create a uniform surface by removing some cement and sand matrix surrounding the stone. The exposed stone yields a textured finish with the color of both matrix and stone. Acid etched finishes can be light, medium or heavy to reveal only a little or a lot of stone. With a light acid wash, the matrix color will dominate; with a deep acid wash, the stone will dominate.
Retarded: Resembling acid etched finishes, retarded finishes, accomplished by using a chemical retarder that keeps the surface cement matrix from hardening, can be used to expose the most aggregate, yielding finishes that can be mostly stone. Retarded finishes can be light, medium, heavy, or exposed aggregate.
Blasted: Sand-blasted or ecologically compatible steel shot-blasted finishes have a similar appearance to acid-etched finishes and are created by using high-pressure sprayed media to remove the cement and sand matrix. The abrasive media used to blast the matrix away from the stone can scratch the stone and may create a slightly duller appearance than acid etched or retarded finishes. Like acid etched finishes, blasted finishes can be light, medium, or heavy.
Honed or Polished: Smooth, mechanically honed or polished surfaces have a uniform appearance and can range from mostly matrix to mostly aggregate finishes. When aggregates are exposed, finishes can resemble natural granite or terrazzo.