Resources for Consumers

Types of Natural Stone

GRANITE

Granite is primarily made of Quartz (35%), Feldspar (45%) and Potassium. Usually has a darker color. Contains very little calcite, if any. Provides a heavy crystalline and granular appearance with mineral grains. It is very hard material and easier to maintain than marble. There are different types of granite depending on the percentage mix of quartz, mica and feldspar. Black granite is known as an Anorthosite. It contains very little quartz and feldspar and has a different composition than true granite. Its durability and resistance to heat and acids used in cooking (lemon juice, vinegar) and will only dull your knives if you cut on it. Granite scores high from a sanitary standpoint - it resists such bacteria as salmonella

Common Uses:
Granite for kitchen counter tops is the #1 natural stone choice as well as bar tops, vanity tops, fireplace surrounds, mantles, hearths, and wraps, table tops, window sills and flooring.


MARBLE

Marble is crystallized limestone that formed when the limestone softened from heat and pressure and re-crystallized into marble where mineral changes occurred. The main consistency is calcium and dolomite. Ranges in many colors and is usually heavily veined and shows lots of grains. Hardness rates from 2.5 to 5 on the MOH Scale.

Marble is classified into three categories: (Stone World)
1. Dolomite: If it has more than 40% magnesium carbonate.
2. Magnesium: If it has between 5% and 40% magnesium carbonate.
3. Calcite: If it has less than 5% magnesium carbonate.

Common Uses:
Marble is a highly decorative stone, common uses are fireplace surrounds, bathtub surrounds, vanity tops, table tops and bases, floors wall panels and architectural elements.


SLATE

Slate is a fine grained metamorphic stone that formed from clay, sedimentary rock shale, and sometimes quartz. Very thin and can break easily. Usually black, grey, or green.

Common uses:
Slate is used for flooring and such bathroom applications as shower stalls, floors and walls.


SERPENTINE

Serpentine is identified by its marks which look like the skin of a serpent. Most popular colors are green and brown. Hardness rates from 2.5 to 4 on the MOH Scale. Contains serpentine minerals has lots of magnesium, and has an igneous origin. Does not always react well to re-crystallization or diamond polishing.

ONYX

Chemically, onyx is similar to alabaster and marble. It's wonderfully translucent but very, very soft.

Onyx is not for walking surfaces, but is great for walls and in the bath.

LIMESTONE

Limestone mainly consists of calcite. It does not show much graining or crystalline structure. It has a smooth granular surface. Varies in hardness. Some dense limestone can be polished. Common colors are black, grey, white, yellow or brown. It is more likely to stain than marble. Limestone is known to contain lime from seawater.

Common uses
Limestone is popular among those people looking for a flat, matte finish. Uses include fire place hearths, mantles and surrounds, address blocks and table tops.


SANDSTONE

Sandstone is a very durable formation of quartz grains (sand). Usually formed in light brown or red colors. Categorized by the most popular sandstone bonding agents such as silica, calcium, clay, and iron oxide.

SOAPSTONE

Soapstone is a very soft stone and uniform in appearance, made of a variety of talc. It is a dense mineral that wears well and is often resistant to stains. Soapstone acquires a patina with age and requires regular oiling for maintenance.

Common uses
Soapstone is used for kitchen countertops.


FOSSILSTONE

Fossilstone is considered a limestone that contains natural fossils such as seashells and plants.


TRAVERTINE

Travertine is a type of limestone usually a cream or reddish color. It is formed through the accumulation of calcite from hot springs. It contains lots of holes that were formed from water flowing through the stone. These holes are often filled with synthetic resins or cements. Requires lots of maintenance if the holes are not filled. Classified as a limestone and a marble.

Common uses
Travertine can be polished or left in its natural matte finish and is often used for flooring, fireplace surrounds, tabletops and bathroom applications.


MAN-MADE

Stones are derived of unnatural mixtures such resin or cement with the additive of stone chips.

Caring for Natural Stone Surfaces

Stone Products

Hanstone - www.hanstoneusa.com

Silestone - www.silestoneusa.com

Educational Resource Link:

Marble Institute of America