Introduction

Nothing exemplifies the beauty and power of nature like natural stone. Let us help you create dramatic, natural beauty in your home.

We have gathered the finest examples of the most sought after stones that will turn your floors, walls, and counters into works of art. Whether in tile or slab form, Lifetime Flooring can get you the deepest colors, richest textures and visual depth in limestone, travertine, marble, slate, and granite.

Each class of rock is a product of Earth’s movement over thousands of years. Natural Stones have always been valued as durable building materials throughout history. Natural Stone is exactly that, a natural element excavated directly from mother earth. Natural Stone offers several desirable advantages to both exterior and interior applications.

Durability

Maintained properly, natural stone will endure for years. Natural stone creates a rich, prestigious upgrade to any room. The use of natural stone on countertops or as flooring significantly enhances the overall look and value to the home.

Variety of Design Options

With multiple colors and types available in natural stone today, design options are limitless. Natural stones can be combined with ceramic tile and other building products to reflect individual creativity and expression.

Various types of stones are excavated from geologic formations located around the world.

Geologic Classifications

Igneous Stones

Igneous stone is the material at the beginning of the entire stone creation process. This geologic category includes granite, which is formed when magma (molten rock within the earth) slowly cools as it moves upwards towards the surface of the earth. The closer and faster the rock deposits move to the surface, the faster the rock cools. The faster the cooling process, the finer the grain structure.

Sedimentary Stones

This group includes travertine and limestone, which were originally formed in seawater or lakes from the sediment fossil remains of animals, plants, shells, and other deposits of rocks and other minerals. The compaction of these various deposit materials and the minerals cementing these deposits together, determine the hardness, density, and porosity of the specific stone.

Metamorphic Stones

Marble and Slate are both included in this group of natural stones. Metamorphic stones are produced from sedimentary or igneous rocks by the action of intense heat and pressure within the earth.

Cleaved or foliated rocks are commonly called “Slates”. A common characteristic of slate is its cleaved plane (layered) formation. The term “Foliated” means the folding or layering of metamorphic rock that occurs when pressure is applied in one direction and creates the layered cleavage texture of slate.

Types of Rock

Sedimentary Rock

Travertine and Limestone: Formed by sediment deposits, such as animals, plants, and minerals

Igneous Rock

Granite: Formed by the cooling of magma (molten rock within the earth)

Metamorphic Rock

Marble and Slate: Formed by intense heat and pressures acting on sedimentary and gneous rock formations

Natural Stone Categories

The current US market for natural stone products is very diverse, however the majority of the products sold are categorized into one of six types. Each type of stone is created differently therefore they each have different physical properties, which make them suitable for specific applications.

All stones are composed of one of two basic groups: Silica or Calcium. These basic minerals are the key considerations to the stones’ applications. Silica based stones such as Granites and Slates are highly resistant to acids and corrosive atmospheric agents carried in rainwater and air, which makes these type of stones good for exterior use.

Calcium Carbonate based stones such as Marble and Limestone are less resistant to acids and atmospheric agents. If used on exterior surfaces, marble and limestone will etch and wear at a faster rate than silica-based stone. This is not to say that calcium carbonate stone should not be used on exterior applications, just that some surface “weathering” effects over time should be anticipated during the early design process.

Types of Polished Finishes

Polishing a stone to a high gloss surface closes or reduces the size of the surface pores of the stone. Reducing the stone’s porosity creates a resistance to soil and staining agents from penetrating the stone’s surface. Generally, the higher the sheen or polish, the more resistant the stone will be to damaging conditions such as moisture, acidic solutions, and air pollutants. Unfortunately, the higher the sheen or polish, the lower the slip resistance or coefficient of friction (COF) of the stone. Harder stones, such as granite will hold their polish longer under traffic than softer stones.

Although there are many other types of surface treatments for natural stone, not all stones are capable of achieving all of the finishes described. Structure, texture, hardness-density. and mineral composition of a specific stone will determine the type of finishes which can be applied.

Honed Surface Finish

A honed finish is a semi-polished, smooth, matte surface finish with less sheen as compared to a polished finish. Because the abrasives used are somewhat coarser than those used to produce a high gloss, polished finish, the surface pores of the stone are more open and exposed than the surface of a polished finish. This increased porosity makes the stone less resistant to the effects of moisture, staining agents, acids, etc. However, a honed surface finish is naturally more slip resistant than a high polished surface. This is an important consideration when using the stone in flooring applications, specifically in wet areas or exterior walkways.

Flamed (Thermal) Surface Finish

A flamed or thermal surface finish is achieved by passing a 2,800°F torch flame over the surface of the stone. This process heats the various minerals and crystals and expands them until they explode or break from the body of the stone. The result of this thermal process is a coarse, irregular surface finish with an exposed pore structure. The flamed finish creates a look and texture which is desirable in certain applications, however this open porosity also exposes the stone to weathering and other moisture-bearing contaminants. Generally, only granites and a few other stones can be successfully flamed due to the amounts of dissimilar minerals present with different coefficients of thermal expansion.

Natural Cleft Surface Finish

A natural cleft finish is a natural surface texture that is produced by splitting or separating stones which posses natural cleaved planes such as slate. The true color of the stone is maintained during the splitting process and the natural cleft surface creates a unique look for a variety of applications. The amount of surface texture will vary with each stone and is primarily determined by the hardness or density of the stone. Less dense stones will cleave with greater irregularity than harder stones, which will cleave in flat, smoother planes.

Benefits of Various Stone Floors

Granite

  • Highly resistant to acids and corrosive agents. a good choice for exterior applications
  • Granular speckled product that is extremely durable, with hardness
  • Very fine grain structure
  • Extremely dense, tight composition
  • Will withstand heavy commercial foot traffic
  • Holds surface polish indefinitely
  • Excellent for flooring and countertops

Slate

  • Layered material formed out of layered stone deposits
  • Can be used in interior and exterior applications and in heavy traffic areas
  • Some slates are prone to surface layer delaminating in wet environments
  • Very fine grain structure
  • Natural cleft surface texture
  • Available in a variety of colors
  • Excellent for interior or exterior applications

Marble

  • Distinctive veins, clouds and mottling appearance
  • Available in variety of colors
  • Normally provided with a highly polished surface
  • Popular for interior applications

Limestone

  • Surface impressions, such as marine fossils, plants, and voids
  • Open grain structure normally honed to satin finish
  • Interior/exterior applications
  • Very durable

Travertine

  • Normally honed to satin finish
  • Interior/exterior applications
  • Open grain structure
  • Subject to freeze/thaw damage

Tumbled Natural Stone

Available in antique color & style variations that is given to travertine, marble, limestone and slate through a mechanical tumbling process.   Smaller pieces of these stones are dumped into a hopper and tumbled together. During the tumbling process, the edges and colors of the stones are softened to an elegant, warm appearance. In addition to the traditional sizes of 3x3, 4x4 and 6x6, larger sizes of 12x12 are also available. Small pieces of these stones are normally sheet mounted into patterns and accent shapes providing for endless design opportunities on floors, walls and counter areas. Tumbled Natural Stones are generally provided in earthy colors of beige, red, black, and green. Sheet mounted pieces allow for easy installation for interior applications.

  • Produced by mechanical tumbling process
  • Variety of stones tumbled together
  • Creates an antique, weathered look-soft edges
  • Mounted patterns, decorative accents
  • Variety of tile sizes available

Technical Information

Natural stone is a product of nature and therefore cannot be weighed or measured in the same manner as manufactured materials like ceramic tile. Each type of stone (marble, slate, granite, limestone and travertine) was created differently, and therefore they have different physical characteristics. However, natural stone is commonly subjected to a variety of tests, which are designed to measure the overall strength of each stone’s suitability for specific applications.

The American Society of Testing & Materials (ASTM) and the Marble Institute of America (MIA) has issued standards for the physical requirements of the natural stones most frequently used in construction. These standards are primarily intended as guidelines for architects, engineers, stone contractors, and other interested parties requiring information for the safe and economical use of natural stone in construction.

Moisture Absorption

Immersing the stone sample in water for 48 hours tests the moisture absorption rate of a stone. The weight difference between the stone in a dry condition and after immersion determines what a percent % of water weight was absorbed by the stone in a 48-hour period. The lower the percentage, the less the moisture absorption rate of the stone. This is useful information when considering how the stone will perform in wet conditions, such as exterior walkways or interior showers.

Density

The density (bulk specific gravity) of a stone is determined by testing the stone sample under the same testing procedures as was used in the moisture absorption test. The before and after weight of the stone sample after immersed in water for 48 hours determines the stones overall density. The results for this test are measured in pounds per cubic foot. As you can see, the density of the stone has a direct bearing on the moisture absorption rate.

Compressive Strength

Measuring the compression strength of a stone determines the load a stone can resist before it will crush. The result of this test is measured in the pounds per square inch (psi). The higher the number, the more pressure the stone will withstand before structural failure. The compressive strength rating is useful in evaluating different stones for floor applications if density, hardness, and comparable installations are also considered.

Abrasion Resistance/Hardness

In addition to the Mohs scratch hardness test (discussed on the ceramic tile page), natural stone uses a similar testing and rating system. The test determines the natural stone’s resistance to foot traffic abrasion when used as a flooring surface. The testing procedure involves measuring the amount of material removed from the surface of a stone sample through 225 revolutions of a grinding wheel. The calculation determines the loss of material from the grinding process; the higher the value, the greater the resistance to abrasion.

Flexural Strength

This test determines the strength of a stone when in tension (also called its bending strength). The test involves placing a load on a sample stone spread between two supports. The load is increased until the stone sample breaks. The resulting test value is expressed in pounds per square inch (psi). The higher the value the more load the stone will withstand.