Clashach Sandstone

Technical Data Sheet
Clashach Sandstone
Clashach Quarry
Birnie, Elgin, Moray, IV30 8SW
Contact : Moray Stone Cutters
Tel. 01343 860244
Grid Reference : NJ 163 702
Compiled May 2000

This data sheet was compiled by the Building Research Establishment (BRE). It is based on data from current tests at BRE (2000). The data sheet was compiled in May 2000. The work was carried out by BRE as part of a Partners in Technology Programme funded by the Department of the Environment, Transport and the Regions and Moray Stone Cutters and does not represent an endorsement of the stone by BRE.

Clashach Quarry is on the Moray Firth coast. The stone has been quarried since 1846, ceasing in the 1940’s at the advent of the Second World War. The present owners have worked the quarry since 1986 and there are good reserves of stone. It is a very hard stone to work and occurs in random sized blocks of size up to 1.8m on bed. It is also a site of special scientific interest with preserved sections of 270 fossilised Permo-Triassic reptilian trackways.

Clashach is a pale yellow buff, non-calcareous, medium grained New Red Sandstone from the Permean age. There is a progressive colour change from the buff to a yellow pink colour across the quarry.

Expected Durability and Performance
It is important that the results from the individual tests are not viewed in isolation. They should be considered together and compared to the performance of the stone in existing buildings and other uses. Sandstone is traditionally acknowledged as generally being a very durable building and paving stone and has been used extensively in many towns and cities in the UK. Clashach sandstone appears to be a very durable stone that has good resistance to acid rain or air pollution. In addition, the negligible weight loss in the sodium sulphate crystallisation test indicates high resistance to salt damage (for example in coastal locations or from de-icing salts). From the frost test the stone should also have good frost resistance. The compressive and flexural strength of the stone is high for a sandstone. The compressive and flexural strength indicate that the stone should be suitable for use in heavily trafficked areas.

Overall, Clashach should be suitable for use in most aspects of construction including flooring, paving, load bearing masonry and cladding. The stone is suitable for areas where a long service life is needed.

Test Results – Clashach Sandstone

in Use
Slip Resistance (Note 1)


Wet. Values > 40 are considered
Abrasion Resistance
(Note 1)

Not tested

Values <23.0 are considered
suitable for use in heavily trafficked
under load
1) Compression(Note 2)

132.3 MPa

Loaded perpendicular
to the bedding plane
ambient humidity
2) Bending (Note 1)

7.6 MPa

Loaded perpendicular to the
bedding plane
ambient humidity

Not tested

Loaded parallel to the
bedding plane
ambient humidity
and Water Absorption
1) Porosity (Note 3)


2) Saturation Coefficient (Note 3)


3) Water Absorption

6.9% (by wt)

4) Bulk specific gravity


Resistance to Frost 
strength after
Freeze/Thaw Test (Note 1)

9.1 MPa

Loaded perpendicular
to the bedding plane
ambient humidity
to Salt
Sodium Sulphate Crystallisation Test
(Note 3)

-0.80% Mean wt loss

Sodium Sulphate Crystallisation Test
(Note 3) (Saturated) 

0.0% Mean wt loss

Resistance to Acidity 
Acid Immersion Test(Note 4)


(Test methods Note 1 = prEn1341, Note 2 = prEn 1342, Note 3 = prEn 1341 /BRE 141, Note 4 = BRE 141)

Tests were carried out at BRE in 2000

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