Strength tests for detecting real stone potential

Natural stones catch all eyes when they are clad over floors and countertops. Be it marble or granite, natural stones are widely used for indoor and outdoor construction works. Natural stone producers offer a variety of stones to make any space look stunning. Beauty is not the only factor, the strength of stone also matters the most. It is the Mohs scale that declares how strong your stone is. While buying any stone, natural stone buyers prefer to go through a lab report showing the level of strength of the stone.

A lab report is like an updated technical documentation that analyses the characteristics and technical aspects of the stone for multiple applications. It would be great to check all aspects of the lab report from natural stone producers. Stone testing types comprise of compressive strength; bending strength; wear, frost, and sliding resistance; density and porosity; and water absorption tests.

Natural stone strength testing

A stone may or may not be useful for a specific application. Do you have any criteria to check this factor? This factor is called stone testing that guides you on the potential of the stone to resist crushing and bending. Natural stone producers use different testing methods for detecting gravity and density, and water absorption potential.

Compressive strength test

The resistance of the natural stone to crushing loads is calculated with this test. It guides you on how a wall stone bears the compressive load and a stone floor withstands human traffic loads, along with heavy objects and furniture. Therefore, compressive strength matters the most as it indicates to the maximum load per withstood by the stone easily. A stone can endure a higher crushing load when it has the following compressive strength, even in dry and wet conditions:

·         1,800 psi (12.45 MPa) to 19,000 psi (131 MPa)

Bending strength test

Bending strength test is vital for checking the extension of the stone in bending comfortably. A higher modulus of rupture or flexural strength declares a superior bending strength. For this, you need a minimum value range (2.8 MPa - 10.3 MPa). This test type also has 3 subtypes:  

•         ASTM C880 for the flexural strength test
•         ASTM C99 test and ASTM C120 (Slate) test
•      Modulus of rupture test

Flexure testing

This test is not very different from the modulus of rupture test, but it is concerned with stone’s thickness and load testing. The real potential of the stone comes out when you check the stone in dry and wet conditions. For this, natural stone producers take at least 5 stone specimens of dry and wet stones. Then, stones have to bear a load until they cave in. There is a formula for calculating the bending strength of slab as per geometry. Moreover, megapascal (MPa) is the unit for expressing the bending strength of any stone.

Wear or abrasion resistance of stone

All stone types are not fit for flooring and countertop applications. You come to know about this with the abrasion test of ASTM C241. The coefficient of friction testing is also useful for getting the right answer. This test results in an index number (ranging between 0 and 100) which is comparative to abraded material’s quantity. The index is determined with the following factors:

•          Abrasion weight loss
•        Average weight
•         The density of the stone

In addition, natural stone producers scrape the stone with the help of a Kessler machine.

Leading natural stone producer Regatta Universal Exports is committed to delivering a wide assortment of strong natural stones that have already passed through different stone strength tests.