Flamed or Thermal-Finished. A thermal finish is often applied to granite and some limestones. It has a rough texture created by passing a flame across the surface, causing pieces of it to pop out. Marble is not available in this finish.
Sandblasted. A sandblasted finish is a rough, dull finish achieved by literally blasting the surface with sand. Sandblasted finishes are very porous, and require a sealer to keep clean.
Hammered. A hammered finish is achieved by striking the surface with a hammer and imprinting it with the pattern of the hammerís face. Hammered finishes are commonly found on granites and limestones.
Natural Cleft. A natural cleft finish, found on the stone as it is taken from the ground, is often left on slate or sandstone.
Sawed. This is the finish produced by sawing. It is characterized by circular saw cuts on the surface.
Tumbled. This rough finish, made by tumbling the stone with abrasives, is usually only found on marble and limestone.
There are also several new finishes coming out, including wet jet and antique.
Resin or Fiberglass Back Stone
Many stone tiles and slabs arrive from the factory with fiberglass or resin on the back to prevent breakage during shipping. This is an indication that you are dealing with a brittle stone that breaks easily. Extreme caution must be exercised when supervising installation. Water-based setting materials will not provide the proper bond unless a 100 percent latex additive is used. Make sure to follow the specification in this manual.
When specifying stone tile, consider the width of the grout joint. Marble and limestone are soft and scratch if sanded grout is used. Also, make sure the grout width does not exceed 1⁄8 in. Granite can handle sanded grout and larger grout widths.
Epoxy grout should be used in any food areas, restrooms, steam showers, etc. Epoxy grout is stainless and does not harbor bacteria. It is therefore the grout of choice in these areas.