There are many types of natural stones, currently our company offers some typical typical stones on the market today such as: marble, marble (marble), … Among thousands of stones, Referring to some stone samples from the stone supplier’s website before visiting the showroom, ice storage and asking consultants is something almost every customer does to color orientation. , striae.
Reading and understanding the stone’s specifications will give you a basic idea of whether the stone is suitable.
- Water absorption
Water absorption is a measure of the porosity of rocks and it can also be an indicator of the possibility of damage when they are frozen. A large water-absorbing stone also means that liquid stains easily penetrate the stone. Everyone wants this coefficient to be as low as possible.
Absorption is expressed as a percentage change in weight due to water absorption. The maximum water absorption is expressed in the specifications of each type of stone. Typical values will range from 0.20% for marble and 12% for the weakest limstone. According to ASTM C97, use at least three rock samples for one stone, after which they are dried and weighed. It is important to select a rock sample that does not crack the surface as these cracks increase water absorption. They are then soaked in water for 48 hours, dried and weighed again. The weight difference between dry specimens and water will be divided by dry weight and multiplied by 100 to give water absorption rate. However, this method is not entirely accurate because the dried specimens will absorb less water, and the use of dry wipes is also not scientific.
- Specific Gravity
Density is the ratio of the density of the rock to the density of water. If a stone has a density of 2.6, it will weigh 2.6 times the amount of water. Density is expressed in pounds per cubic foot (lb / ft3) or kg per cubic meter (kg / m3). The density of lb / ft3 can be determined by multiplying the weight of the natural stone by 62.4 (weight of 1 cubic foot of water) or by multiplying 1000 by the density of kg / m3. One lb / ft3 is equal to 16.02 kg / m3.
- Compressive Strength
Compressive strength is a measure of endurance for destructive loads. For example, if a stone wall is built, the rock at the bottom must withstand the weight of the rock. Paving stones must be able to withstand lots of people and furniture on the floor. Compressive strength is the maximum load per unit area that a natural stone can withstand without damage. High compressive strength suggests that the rock can withstand a larger load. The value of natural stone ranges from 1,800 psi (12.45 MPa) with marble to 19,000 psi (131 Mpa) with marble.
To determine compressive strength, use at least 5 test pieces for testing in accordance with ASTM 170. Each sheet must be 2 “to 3” in thickness. The face of the test piece shall be flat, smooth, free from cracks, cracked and polished or honed without fingerprints. Any mistake can make their compressive strength inaccurate.
- Hardness (Moh’s Scale):
Determining the hardness of natural stone helps us know which items to use. Hardness is a measure of mineral abrasion and is measured on a standard scale – Mohs Scale of Hardness. The Mohs Scale is named after Frederick Mohs (1773-1839), a German mineralogist.
You often hear Eurostone’s staff advise that if the hardness of a diamond is 10, the marble is 6, 7 and the marble is 3, 4. These are words based on the Mohs hardness scale, This scale indicates diamonds H = 10 (highest) and Talc H = 1 (lowest). The higher the Mohs number, the harder it is for the natural stone to be and vice versa. Typically sa trung marble is 6.5, while marble types: Cararra, Calacatta, Thassos at level 4.