Our newly refurbished Natural Stone Testing Laboratory has allowed us to expand our materials testing services as well as increase production and better improve on our turnaround of samples. Our Natural Stone Laboratory is equipped to test for a comprehensive range of geological, physical and mechanical properties on rock, natural stone and armour stone.

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Natural Stone Tests by ACS:

Test Method What is shows
Abrasion Resistance BS EN 14157 This test simulates long term wear effects on natural stone products (e.g. pedestrian trafficked areas) using an abrasive flow medium and abrasion wheel.
Breaking Load and Dowel Hole BS EN 13364 This test gives a breaking load of a pin which is grout anchored into a natural stone specimen. Typically done on proposed cladding stone destined for interior and exterior fixings.
Flexural Strength under concentrated load BS EN 12372 This test gives a flexural strength from a single load point. Typically done on proposed cladding stone for ventilated facades. This test can also be done in conjunction with the frost resistance test to determine strength deterioration over a cyclic temperature pattern.
Flexural strength under constant moment BS EN 13161 This test gives a flexural strength from two load points. Typically done on proposed cladding stone for ventilated facades. This test can also be done in conjunction with the frost resistance test to determine strength deterioration over a cyclic temperature pattern.
Frost Resistance BS EN 12371 This test subjects natural stone specimens to a cyclic temperature pattern of freezing air and thawing in water. Specimens are either “Scored” visually during test or tested mechanically (Flexural strength or uniaxial compressive strength) to determine performance.
Petrographic Examination BS EN 12407 This test involves subjecting a specimen of the natural stone to visual and low power microscopy. The analysis gives information of constituents present in the stone in addition to any features of interest. This could include minerals which give rise to discolouration’s in the stone.
Point Load Strength Test (Rock) IRSM This test is used to classify the strength of rock materials on samples with little to no preparation. This test can also be used to predict strengths with correlated specimens (Uniaxial compressive strength).
Real and Apparent Density (total and open porosity) BS EN 1936 This test gives a density of stone and the porosity (Open voids ratio to volume). The density can be used to determine weight per volume for design purposes. The porosity can give an indication of the absorption properties. High porosity materials may also exhibit deterioration under frost cycling and salt crystallisation testing.
Resistance to Salt Crystallisation BS EN 12370 This test involves cycling specimens between an chemical solution, Air drying and then cooling. This cycle is run 15 times and then reported as a % Mass change. This test can be used in conjunction with the Frost Resistance test to determine durability over time in open weather conditions.
Slip Resistance by pendulum tester BS EN 14231 This test involves using a swing mounted rubber slider to determine the slip resistance of a surface. The higher the number, the less slippery the surface is. This can be done over different surface finishes (Polished, honed, sandblasted) to determine suitability for pedestrian areas. This test can also be conducted IN FIELD on natural stone products already laid.
Water absorption at atmospheric pressure BS EN 13755 This test gives a water absorption by weight (%) of natural stone. This can be used to calculate the saturated weight of the natural stone for use in the design phase in addition to indicating expected water addition for durability purposes (e.g. material alteration via mechanically or chemically).
Water absorption coefficient by capillarity BS EN 1925 This test gives a water absorption by unit area of natural stone in contact with water. This can be used in conjunction with other tests to determine suitability of the stone for the intended use (E.g. cladding, tiles etc).
Uniaxial compressive strength BS EN 1926 This test gives a compressive strength (MPa) of either cube or cylindrical specimens. This can be used in the design stage for structural or load bearing elements. This can also be used in addition to the frost resistance test to determine performance over time when exposed to cyclic freezing and thawing.

Frequently Asked Questions

Why is natural stone testing important?

Natural stone testing is crucial for understanding the geological, physical, and mechanical properties of stone materials planned for construction or found on existing sites. These tests enable informed decision-making in the design stage by assessing the stone’s potential durability and suitability for pavements, floors, steps, and other locations likely to experience foot traffic.

What is a petrographic examination?

In natural stone testing, petrographic examination uses microscopes to determine a sample’s mineralogical and chemical characteristics. Samples for petrographic examination can be extracted from cores or lump samples and are usually prepared with resin.

How do you test the water absorption of stone?

Water absorption analysis is a natural stone testing method used to identify the water absorption level by weight (%) or unit area of the natural stone in contact with water. For water absorption by weight, a stone sample is cut to a specified size, kiln-dried, and weighed before being immersed in water and weighed again.

What is the pendulum test for slip resistance?

The pendulum test for slip resistance is an established natural stone testing procedure that measures the dynamic friction of the surface of the stone. This test requires a slider to be mounted at the end of a pendulum arm, imitating the action of slipping.

The results are measured under a “Pendulum Test Value” (PTV) and can be used to determine the suitability of the material for pedestrian areas.

ACS Services

Please see below for a list of the services provided by ACS:

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Geo-Environmental Consultancy

The ACS Geo-Environmental Consultancy Department has been operating as part of ACS for over 10 years.

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On-Site Testing Services

ACS offers a comprehensive range of professional on-site testing, all carried out by our fully trained site technicians.

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Aggregates and Soils Testing

From our main laboratory in Poole, Dorset, ACS provide quality testing and material consultancy for the construction and civil engineering industry.

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Bituminous Testing

ACS carries out testing on new bituminous binder material and testing on hardened material for physical and chemical properties. Circa pre 1980’s Tar (Carcinogenic effects) was also used as a binder, ACS staff can sample and test materials to assess if Tar was used.

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Concrete Testing

Concrete was the first service to be offered by ACS back in 1987. Since then, we have increased our scope to cover a wide range of UKAS Accredited testing methods on fresh and hardened concrete.

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Mortar and Screed Testing

ACS can sample and test new and hardened mortar. Hardened mortar for mix proportions and constituents, new mortar for compressive and flexural strength.

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Contamination and WAC Testing

At ACS we offer an efficient and reliable chemical analysis service for waste soils and construction materials using various test solids and leaching procedures specified by the Environment Agency.

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Chemical Testing

The ACS chemical laboratory was established in 2007. It complements the physical materials testing service provided by ACS by offering a range of chemical analytical services.

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Leachate and Water Analysis

Our purpose-built analytical laboratory enables ACS to provide a comprehensive sampling, monitoring and analysis service on a wide range of leachate and water samples.

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Natural Stone Testing

Our newly refurbished stone testing laboratory has given us the opportunity to expand our testing scope. In addition, we have increased production and improved on our turnaround of samples.

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Site Laboratory Services

Over the last 35 years, ACS have supplied custom fitted site laboratories with technicians to many construction sites and projects worldwide.

Persistent Organic Pollutants

Our experienced lab technicians can provide detailed and accurate analysis of Persistent Organic Pollutants (POPs) in almost any sample matrix in line with the Stockholm Convention.

Energy From Waste

Experts in Energy from Waste residues, ACS offers a full range of services, including gasification, pyrolysis, syngas and tar sampling, and analysis and interpretation of analytical results for IBA and APCr.

RoHS Compliance Testing

At ACS, we undertake rigorous RoHS compliance testing to identify and quantify any contaminants in your shredded waste, ensuring your product meets strict RoHS requirements.

Energy Supply, Generation & Regulation

Our highly skilled team provide industry-leading waste fuel testing services for RDF, SRF, MSW, and Solid Biomass, helping you save costs and meet compliance standards for total peace of mind.


If you require a collection that is outside of our usual range, please feel free to call us on 01202 622858.
Or contact us and we will do our best to accommodate your requirements.