Wattscliffe Lilac Specification

General
The quarry is about three-quarters of a mile from Elton on the road from Elton to Alport. It was opened in the 19th century to supply grindstones. Records show that it has been used for buildings since at least 1926.

Petrography
Wattscliffe Lilac Gritstone is a sandstone is from the Millstone Grit of Carboniferous age. It is a fine- to medium-grained stone, lilac to pink in colour with occasional buff/white intrusions. The average block sizes are 2000mm x 1000mm x 1000mm.

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. Sandstones from the Millstone Grit are traditionally acknowledged as generally being a very durable building and paving stone and have been used extensively in many towns and cities in the UK. Wattscliffe Gritstone appears to be a durable stone that is not effected by acid rain or air pollution. Most sandstones have good frost resistance. The failure in the harsh saturated sodium sulphate crystallisation test usually indicates susceptibility to salt damage (for example in coastal locations or from de-icing salts) but evidence from use on the coast in the north-west of England shows that it performs well in this type of environment. The compressive strength of the stone is typical of the range for sandstones and is comparable with that for the stronger UK limestones.

Overall, Wattscliffe should be suitable for use in most aspects of load bearing masonry and cladding but should not be used in areas where a long service life is needed in locations with a high salt concentrations.

Test Results – Wattscliffe

Safety in Use
Slip Resistance (Note 1)

Not determined

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

Not determined

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

79.1 MPa

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

4.8 MPa

Loaded perpendicular to the bedding plane ambient humidity

7.6 MPa

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

12.49%

2) Saturation Coefficient (Note 3)

0.64

3) Water Absorption

3.44 % (by wt)

4) Bulk specific gravity

2312kg/m3

Resistance to Frost
Freeze/Thaw Test (Note 1)

Not determined

Note: the stone Passed Test B using DIN 52 104
Resistance to Salt
Sodium Sulphate Crystallisation Test (Note 3)

-0.44% Mean wt loss

Sodium Sulphate Crystallisation Test (Note 14) (saturated)

Mean wt loss

All cubes failed before the end of the test
Resistance to Acidity
Acid Immersion Test(Note 4)

Pass

All samples passed the test with no splitting or delamination