Granite or Marble?

Natural stone in your home is earth’s beautiful piece having variety of types and characteristics. It’s popular today in different applications due to its durability and maintenance. It’s imperative to remember however, that different stones, although similar in appearance, may have different characteristics, and as a result have varying tolerances. It’s important to know what stone you have in your home and apply appropriate maintenance procedures, and precautions in order for it to serve for the life.

Different Types of Natural Stones Used in Residential Applications

Granite

Granite is considered “hard” rock. It is an ignenous rock which means that at one time during its development, it was melted like volcanic lava. Unlike lava, however, this melted (or molten) rock never reached the surface. It remained trapped inside, where it slowly cooled and crystallized, resulting in a very uniform, speckled stone that ranges in colour from black and gray tones to pinks, browns, and reds. It is formed deep beneath the earth’s crust, and rises from the molten magma, forming at temperatures in the thousands of degrees.

Granite is especially popular for use as flooring or countertops. Unlike marble, granite is a relatively hard, non- porous, natural stone. It is relatively resistant to most household kitchen products and handles heat extremely well. Some granite however, can be stained by some liquids or darkened by oils. It is therefore best to practice preventative maintenance procedures, seen on following pages. Care involves regular cleaning with warm, soapy water.

In a study conducted by the Hospitality Institute of Technology and Management, measuring the bacteria resistance capacity of common countertop materials, granite came second to stainless steel.

Marble

Marble has been valued for thousands of years for its rich palette of beautiful colours and is perfect pretty much anywhere in the house, especially for foyers, fireplaces and bathroom walls, floors and vanities. Marble is usually polished to a mirror-like shine and runs the colour gamut from white and muted beiges to browns, rich reds and greens.

True marbles are generally white or whitish, sometimes translucent, with some veining or colour provided by other minerals present during the process of metamorphosis. Foreign substances often entered the stone during this process, creating an infinite variety of colours, asters, and veining. Marble is a lot like snowflakes, no two pieces are exactly alike. Marble also has a variety of densities, many are lighter than granite, while others may be similar. Most marble has a higher absorption rate and lower abrasion resistance compared to granite.

Marble’s kitchen use should be considered carefully, due to oil absorption. When polished, it requires high level of maintenance when used as flooring in high traffic areas.

Marbles range in hardness from 4-5 on the tenpoint MOHS scale (diamonds are 10; granites are ±7).

Slate

Slate is a fine grained, crystalline rock derived from sediments of clay and fine silt which were deposited on ancient sea bottoms. Superimposed materials gradually consolidated the sedimentary particles into bedded deposits of shale. Mountain building forces subsequently folded, crumpled, and compressed the shale.

At the same time, intense heat and pressure changed the original clays into new minerals such as mica, chlorite, and quartz. By such mechanical and chemical processes bedded clays were transformed, or metamorphosed, into slate, whole geologic ages being consumed in the process. Slates vary in composition, structure, and durability because the degree to which their determinant minerals have been altered is neither uniform nor consistent.

Limestone

Limestone has been used as exterior building cladding since time immemorial. Though most of it is gone, looted to build other structures, the Great Pyramids in Egypt were originally clad in smooth, perhaps even polished, limestone, as are many of the great cathedrals of Europe, such as Notre Dame in Paris. Sadly, many of these have fallen victim to a more modern menace, the acids found in polluted air, which have actually dissolved the surfaces and deteriorated the stone.

Limestone is light in density and has a higher absorption rate and lower abrasion resistance than most marble and all granites. Limestone will require more time consuming maintenance than harder stones. Beware of limestone for high stress areas.

Limestone range in hardness from 3-7 on the tenpoint MOHS scale (diamonds are 10; granites are ±7).

Marble, Slate and Limestone are considered “soft” stones.

Stone Finishes

The finish of a stone contributes a great deal to its beauty, its durability and its use in a variety of applications. Here’s some information on finishes:

Polished: Large machines progressively grind the stone to a specular, mirror-like finish.

Honed: This less formal, softer-appearing stone has a matte or satin finish.

Flamed: Blowtorch-strength heat is applied to the surface to create a deeply textured surface ideal for outside use.

Tumbled: This stone is tumbled with sand, pebbles or steel bearings to create a weathered, aged finish.

Filled: When travertine is used for tiles and slabs, it is usually “filled”—that is, the surface holes are filled with cement or sometimes epoxy, and then polished or honed like any other stone tiles or slabs.

Preventative Maintenance

Proper preventive and routine maintenance is required to keep stone in good condition.

First and foremost is to “seal” your countertop and floor. By sealing the stone, you are reducing stone’s absorption qualities. Dont forget, it is still the natural stone and has the absorption quality just reduced a bit. If you let any liquid sit on the stone, it will get absorbed and show as a stain on the surface.

Provide floor mats or area rugs inside and outside entrances to prevent dirt,
grit, acidic rain water, rock salt, and ice melt from being dragged across
stone floor. Be sure underside of mats and rugs have nonslip surface.
Keep floor dirt and dust free. Dirt particles can scratch the stone and dust
makes the floor slippery. High traffic areas should be cleaned more often.
Walkways outside of entrances should be swept to prevent dirt particles from entering building.
Clean spills immediately before they stain. Keep water from spilling on the surface, especially around drinking fountains and planters
Keep metal objects away from marble. A metal can could rust and stain marble if exposed to moisture.
Practice regular and appropriate maintenance procedures.
A good rule is to not use anything on stone that you wouldn’t use on your hands.
Do not cut directly on your stone counter top. This can cause deep and permanent scratches to appear.
Avoid directly dropping heavy or sharp objects on your counters.
Avoid flame or applying heat directly to your stone counter tops.
NOTE
Soft stone can be damaged by acids. With polished surfaces, permanent dull areas can develop if exposed. Materials such as wine, fruit juice, cola, vinegar, lemon juice should be kept away from marble, as well as scouring powders which contain abrasives.

Marble isn’t quite as worry-free as granite. It has a softer, less stain-resistant surface than granite and should be treated like a fine piece of wood. Spills should be wiped up immediately, coasters should be placed under beverages to avoid staining and etching. Marble is especially susceptible to damage from citric acids, alcohol’s, and oils. Routine maintenance should include dry dusting with a soft cloth as needed.

Regular Maintenance

Dust mop frequently with clean, non-treated cloths/mops. Dirt and grit are abrasive and scratch stone. Do not use vacuum cleaners on stone floors. The plastic attachments and wheels will scratch the surface. Higher traffic areas need to be cleaned more often.
Clean stone with appropriate cleansers. Do not use vinegar, lemon juice, cleaners that contain acid, or abrasive cleaners. Any cleaning product should be tested in an inconspicuous location to ensure compatibility with the material and to avoid damage.