MARBLE

Marble has been valued for thousands of years for its rich palette of beautiful colours and appearance and is suitable for most areas in the home. Marble stones consist of limestone that has undergone heat and pressure. A transformation process takes place when the weight of overlying material, pressure from crystal collisions and heat from the earth’s core generate temperatures in excess of 1800ºF.Texture of marble depends on the form, size and uniformity of grains. The element components of marble determine the colour of the stone. One of the most commonly known of natural stones, marble is known for its vein pattern and large selection of colours, normally polished to a mirror-like shine. Often used in areas such as foyers, fireplaces and bathrooms, care does need to be taken when choosing marble for a high traffic area or kitchen countertops which may be exposed to etching substances or harsh chemicals. Marble in any application should be sealed with a penetrating sealer to prevent spills etc from staining the stone.

ITALIAN NAMES AND COLOUR

ITALIAN NAME ENGLISH COLOUR

• Azzuro – Blue
• Breccia – Broken Pieces
• Dorato/D’oro – Gold
• Fiore – Flower
• Giallo – Yellow
• Negro/Nero – Black
• Perla/Perlato – Pearl
• Rosa – Pink
• Rosso – Red
• Verde – Green
• Bianco – White

Example:

Negro Marquina- Black Limestone from Marquina, Spain. Bianco Carrara- White Marble from Carrara, Italy. 

HARDNESS OF STONE

Marble is a relatively soft stone. On a measurement of hardness (MOHS), marble is approximately a three out of ten. Marble is made of calcium, just like your teeth. If you eat something to hard you will break your tooth. If you eat a lot of sugar you will get a cavity. Stone reacts the same way. If an improper chemical is applied to the surface, corrosion will begin to form cavities in the stone.
Listed below is the famous Measurement of Hardness (MOH) Scale for stone. This is a guide developed in the 1800′s which helps evaluate the strengths and weaknesses of the stone being used. For example, softer stones would require the use of a less active chemical and a more frequent dust mopping program.

Measurement of Hardness Scale

1. Talc
2. Gypsum
3. Calcite (Most Marbles)
4. Fluorite
5. Apatite
6. Feldspar (Granite)
7. Quartz (Granite)
8. Topaz
9. Corundum
10. Diamond

The objective of the MOH Scale is to measure stones resistance to hardness. When sediment and grit are harder than the surface, they will scratch and harm the stone. For example, a piece of hard plastic is about a 2.0. It will not scratch #3 Calcite (Marble). However, a piece of sand that measures a 6, will scratch #3 Calcite but will not scratch #7 Quartz which is Granite. The harder the stone, the more resistant it is to abrasion. Exterior sediment that is tracked in to buildings approximately measures from 3.0 to 7.0.

Stones: 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 formed from limestone or dolomite that has undergone enough heat and pressure to metamorphose into a crystalline structure. This metamorphosis takes place when temperatures in excess of 1800ºF are generated by the weight of overlying material, pressure from crustal collisions and heat from the earth’s core. True marbles are generally white or whitish, sometimes translucent, with some veining or colour provided by other minerals present during the process of metamorphosis. Breccias, or brecciated marbles, such as Breccia Oniciata or Breche Nouvelle, are stones which have been broken up by earth movement, landslides and cave-ins, and re-cemented with various dissolved minerals such as silicates, resulting in the characteristic “broken” appearance. Most green marbles on the market are technically not marble, but serpentinites, or serpentines, as they are more commonly called. These include the “jades” from Taiwan, and the very hard Verde Antique from Vermont. Because they are chemically more closely related to basalt and other mantle rocks, they aren’t subject to etching and tend to be a bit harder than other stones generally classified as marble. Marbles range in hardness from 4-5 on the ten-point MOHS scale (diamonds are 10; granites are ±7), making it perfect for most areas of the home. Care does need to be taken, however when choosing material for a high-traffic area or kitchen countertops which might be subject to etching substances. Like any stone, marble should be sealed with a penetrating sealer to prevent stains from penetrating into the stone.

SURFACE TEXTURES

There are many different types of stone available today. When stone is ordered, it is fabricated with a particular type of surface. There are six main types of surfaces that are selected:

Honed: Provides a flat to low sheen gloss. Different levels of gloss can be selected. This surface is very smooth, but often very porous. This texture is common in high traffic buildings. Honed floors should always be protected with Stoneguard Penetrating Sealer because it has wide-open pores. Honed stone colours are not as vibrant as a polished stone.

Polished: A glossy surface that wears away with time due to heavy foot traffic, and using improper maintenance procedures. This surface is very smooth and not very porous. The reflectivity of polished crystals brings out the brilliant colours and grains of natural stone. The shine comes from the natural reflection of the stone’s crystals. The polish is provided by polishing bricks and polishing powders that are used during fabrication. The shine is not from a coating.

Flamed: A rough surface that is developed through intense heat. During fabrication, the stone is heated up and the crystals begin to pop, thus forming a rough surface. This surface is very porous and must be treated with Stoneguard.

Tumbled: A slightly rough texture that is achieved by tumbling small pieces of marble, limestone, and sometimes granite, to achieve an archaic/worn appearance. It often requires an application of Stone Colour Enhancer to bring out the colours.

Sand Blasted: This surface is the result of a pressurized flow of sand and water that provides a textured surface with a matte gloss.

Sawn: A process performed by using a gang saw.

Bush Hammered: A pounding action that develops a textured surface. The degree of roughness can be selected.