Coombefield Whitbed
For a larger view click on image.
Description
A tightly grained Portland stone with medium shell content.
Coombefield whitbed is durable and suitable for all most applications as a general building stone including, paving and copings.
It is easily carved and can be shaped to suit most applications.
This quarry is now coming to the end of its working life and while we still have reasonable stocks, it should not be considered for large projects.
Petrography
Portland Oolitic Limestone
Principally formed from micritic ooids in a spare micritic matrix, the stone contains many shell fragments in the size range 1mm to 10mm. Some compaction of the ooids is present but the matrix exhibits a high intergranular porosity with interlinking of pores. No clay or other minerals are apparent.
Durability & Weathering
Coombefield Whitbed is known to be a durable building stone and has been used extensively within the United Kingdom and Abroad. It exhibits a low saturation coefficient, good strength and good resistance to salt crystallisation.
Historic use indicates that it is capable of service life well in excess of 60 years providing that exposure conditions are not subject to frequent severe frosts or high concentrations of sulphur dioxide and that good stone detailing methods are employed to give best protection from surface water ingress.
It is estimated that the likely weathering rate of this stone would lie between 1mm to 2mm per 100 years in normal exposure conditions.
Physical Characteristics
Colour: Buff White Texture: Medium Grained
Sizes Available:- Maximum Typical Range
Bed Height: 1800mm 600mm – 1500mm
Length: 4000mm 800mm – 2800mm
Block Size: 6.2 m3 0.40 m3 – 3.8 m3
Please note that limestone is a natural material and is subject to variations in colour, pattern and/or texture.
Only full bed height samples each numbered and acknowledged by all parties involved could be considered contractual.
To that end it is essential that a visit to our quarries to select the range required is advised.