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PROMOTIONAL SALE: Silestone Blanco Matrix | $50 per sqft installed

Evaluate Natural Stone

 

HOW NATURAL STONE IS EVALUATED?

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Dimensional stone – that is, stone used for counter, flooring, walls, etc. – is bought and sold based on a grading system. The grading criteria, like diamonds, are generally determined by on-site experts, such as gemologists, geologists, and buyers/traders with many years of experience.

Diamonds however, are only one type of stone – diamond. It is much easier to establish a quantifiable grading system when dealing with one type of stone. This is the reason why the Gemological Institute of America (GIA) created the system now known as the 4Cs – color, cut, clarity, and carat. This system is generally used for consumer purchases, whereas most wholesale diamond transactions are bought and sold by eye and experience.

Similarly, dimensional stone is evaluated for varying criteria, including its density, porosity, color, uniqueness, and closeness to the reference standard. The major difference however, is that over 2,000 types of stone are bought and sold in the commercial market. Either a diamond is, or is not a diamond, there is no grey area. Dimensional stone however, may be classified in a number of different ways. Because of this, it is nearly impossible to create a grading system that would work universally.

Consequently, dimensional stone is bought and sold by experts who understand what characteristics it should have. A particular type of stone will almost always come from the same quarry, region, or mountain range. That stone is evaluated at the quarry for these characteristics and given a “grade” ranging from 1 – 4, with a “commercial” quality being between grades 1 and 2. Other factors come into play as well including: the level of polish, the quality of the stone’s finish, and if a resin finish applied.

So what does this mean to the end-user? The best grades of stone almost always come from the deepest quarrying positions. The deeper the stone, the older it is, and the more heat and pressure it has been under during its formation stage. These conditions create the most dense and least porous of stones, two of the most desirous traits. The denser and less porous a stone is translates to its hardness, durability, scratch and liquid resistance.

The best of these stones are bought and sold as grade 1.
All of MARBLEX materials are imported directly from the quarry and are the finest grade 1 material available.

It is also important to note that every slab, from every block, is slightly different. While some species of stone are very consistent from slab to slab, others vary wildly. Because of these variations, MARBLEX recommends that customers pick their individual slabs at our warehouse.