Portland Stone, particularly the Basebed, is a fine-grained, durable Limestone that is relatively easily worked, and this has therefore encouraged its use for Sculptures, Headstones, and other ornate uses.
We particularly encourage sculptors to visit the quarry and select the actual block from the mine stock. This gives us an opportunity to discuss whether it is practical to complete some additional cutting in the quarry or the factory to save time-consuming hand work.
It is also important to remember that the blocks are measured to the Eurocode standard, the greatest cube that could be cut from the raw block, so as much as 50% extra stone at 2.5 tonne per cubic metre should be allowed for when calculating the weight from the measure.
It is important that the base or supporting structure is properly constructed to take the weight of the stone and there is access for the delivery vehicle.
The location needs to be carefully assessed to ensure that it is suitable for the stone; overhanging trees may encourage algae growth or bird fowling, whereas a low-lying area may be subject to flooding or puddling of water with potential staining and salt crystallisation damage.
Any bedding or pointing would typically be 1: 2: 8 or 9, white cement, lime, and Portland Stone Dust. Lime mortars may be appropriate in some applications.
Portland Basebed has been traditional reserved for fine carving and memorial work and remains the stone of choice for traditional churchyard headstones.
The National Association of Memorial Masons (NAMM) has created regulations which must be adhered to when a headstone is being installed to ensure that cannot fall or be pushed over. Their members will also be able to seek the permission of the cemetery or churchyard for the particular design, and manufacture can either be completed by Albion Stone or the NAMM member.
Portland Stone can be used for other ornate uses such as balustrading, seating, tables, and urns. The design and the fixing should be completed by operatives experienced with Portland Stone and there is some useful background information in the Natural Stone Masonry in modern Scottish Construction.
The stone will not require cleaning to safeguard its durability; cleaning is purely a cosmetic requirement.
The effects of algae growth and bird fouling can be limited with a regular cleaning regime using water with a soft bristled brush. For the removal of this, and more ingrained contamination call the Lithofin Technical Line for specific guidance on cleaning this type of surface.
The Commonwealth War Graves Commission (CWGC) now use enzyme-based products to clean Portland stone headstones, memorials and cemetery features after extensive laboratory and field tests. These far more environmentally-friendly products have allowed the CWGC to move away from using ammonia-based biocides and after 3-years of use in Belgium, the Netherlands and Germany have now been introduced across France and the UK.
Albion Stone, a fourth generation family business pride ourselves on having a helpful and skilled workforce as well as modern and traditional manufacturing process to enable us to produce the highest quality Portland Stone with minimal environmental impact.