This data sheet was compiled by the Building Research Establishment (BRE). Where possible, data collected in earlier surveys has been used to help interpret the test results. The data sheet was compiled in September 1999 using the results of tests carried out to the proposed European Standards. 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 Rattee and Kett and does not represent an endorsement of the stone by BRE.

General
The quarry is to the left of the road between Clipsham and Careby about 1 mile from Clipsham to the north of Stamford. The overburden is up to 15m deep in places and the overall height of the worked face is around xm. The maximum blocks size at the quarry is up to 1800mm height on bed but 900 - 1200mm is more normal.

Petrography 
The stone is an oolithic limestone from the Lincolnshire Limestone formation of middle Jurassic age. It is a creamy-brown coloured stone with many pieces of shell. Some blocks can contain a substantial amount of the harder blue stone.

Expected Durability and Performance 
It is important that the results from the sodium sulphate crystallisation tests are not viewed in isolation. They should be considered with the results from the porosity and water absorption tests and the performance of the stone in existing buildings. Stone from the Clipsham quarries has a long traditionally used as building stone in the region and in Oxford. The porosity indicates a stone that will have good resistance to weathering. The sodium sulphate crystallisation result also indicates that the stone will have good resistance to salt damage and that it will perform well in all but the most exposed locations where it may it may require some extra protection or careful design and detailing to shed water. The strength is towards the lower end of the range for limestones but the performance should satisfactory if the relevant British Standards are followed.

Test Results - Clipsham Holywell Quarry

Safety in Use
Slip Resistance (Note 1)	N.D.	Values > 40 are considered safe
Abrasion Resistance (Note 1)	N.D.	Values <23.0 are considered suitable for use in heavily trafficked areas
Strength under load
1) Compression(Note 2)	27.0 MPa	Loaded perpendicular to the bedding plane ambient humidity
2) Bending (Note 1)	4.7 MPa	Loaded perpendicular to the bedding plane ambient humidity
	2.5 MPa	Loaded parallel to the bedding plane ambient humidity
Porosity and Water Absorption
1) Porosity (Note 3)	18.8%
2) Saturation Coefficient (Note 3)	0.81
3) Water Absorption	6.9% (by wt)
4) Bulk specific gravity	2207kg/m3
Resistance to Frost
Freeze/Thaw Test (Note 1)	N.D.
Resistance to Salt
Sodium Sulphate Crystallisation Test (Note 3)	19.12% Mean wt loss

(Test methods Note 1 = EN1341, Note 2 = EN 1342, Note 3 = EN 1341 /BRE 141, Note 4 = BRE 141)

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