Why are some stones more expensive than others?
Stones that are harder and denser are more difficult and expensive to quarry and process. Quarrying methods vary as well; stones may be quarried below ground, which is more expensive than above ground. Also, since natural stone is quarried all over the world, long distance shipping factors into the price.
Why are bigger sizes more expensive?
The larger the stone, the more difficult it is to process, handle, pack, and transport. Larger sizes also tend to have a higher amount of waste compared to the part that is used, which makes them more expensive.
What are different kinds/types of stone finishes?
The different types of stone finishes include:
Natural Cleft: Unique to slate, it has a slightly uneven surface that is still usable for flooring. This finish cannot be created, but occurs naturally as the layers of slate are quarried. One side (back side) can be gauged to facilitate ease of “thin set” installation. Some marbles, sandstones and limestones are available with heavy clefting, suitable for wall installations only.
Polished: Grinding, sanding, and buffing produces a high gloss, mirror-like surface.
Honed: Grinding and sanding produces a smooth, yet not glossy finish. This is best for low maintenance, high traffic applications.
Flamed: A flamed surface is achieved by subjecting the stone to the high temperature flame of a torch and burning most of the carbon content, leaving textured quartzites with gentle coloration.
Sandblasted: This is a rough, but tidy look created by applying a high pressure blast of sand to the stone’s surface.
River Wash: This finish is often given to granites, and provides a non-slippery surface while retaining the coloration and grain structure of the stone.
Leather: Available only in Melange marble, this finish gives the stone a suede look and feel. This texture is smooth and slip-resistant.
Tumbled: Tumbling stones in a solution of sand, water and mild acid creates an old world, weathered look.
Split Face: Mainly used for cladding, this is achieved by splitting stone either by hand or by machine so that the surface exhibits a natural quarry texture. It has a flat back and uneven front surface, and creates the uneven look of protruding bricks.
Fleuri Cut: This is achieved by cutting quarried marble or stone parallel to the natural bedding plane.
Cross-Cut: The cross-cut method involves end-cutting blocks of travertine to display a less linear, more rounded “wavy” pattern.
Vein Cut: Opposite of cross-cutting, the veining of the stone is shown as a linear pattern.
Veneer Stone: Any stone used as a decorative facing material as wall cladding which is not meant to be load-bearing. Veneer may be made from different finishes, such as split face, cleft, honed, polished, flamed or tumbled.
Gauged vs. Un-gauged: Slate is cleft out of blocks to form tiles. When it is cleft by machine or saw, it is gauged because a uniform thickness is formed. Ungauged stone is hand-cleft and its thickness may vary up to 5/8 of an inch.
Why are some finishes preferred for a particular application?
There are three important reasons for choosing one finish over another in certain applications:
Safety: When choosing flooring, it's important to choose a slip-resistant surface for outdoor applications where the floor may become wet. Highly polished surfaces should only be used for interior floors. Also, highly clefted, uneven surfaces may cause a tripping hazard when used for flooring.
Maintenance: Softer, less dense stones such as marble or limestone are unsuitable for high traffic areas because they will quickly become dull and will need frequent restoration to maintain their finish.
Usability: The application should be consistent with the type of finish selected. A rough finish such as flamed would be a poor choice for countertops, due to the difficulty in cleaning it. Clefted material should not be used for tabletops, because it would present an uneven surface.
Granite, marble, and slate may be available in nearly any color, so it may be possible to specify stone color, with some tolerance for shade differences. Not all stones are available in all colors, however. Travertines, for example, are only found in shades of beige, yellow, and gold.
Each stone is unique, and some types of stone display more variation between the pieces than others. Granites show little variation in color, but may have differing patterns and grain density. Slates tend to show a wide variation in color, even within the same pallet of stone.