Footpath to Janet's Foss and Yorkstone Slabs - geograph

Footpath_to_Janet's_Foss_near_Weet_Close_Bridge_-_geograph

Yorkstone or York stone is a variety of

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

, specifically from quarries in

Yorkshire Yorkshire ( ; abbreviated Yorks), formally known as the County of York, is a historic county in northern England and by far the largest in the United Kingdom. Because of its large area in comparison with other English counties, functions hav ...

that have been worked since the

middle ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

. Yorkstone is a tight grained,

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonif ...

sedimentary rock Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

. The stone consists of

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical fo ...

mica Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is ...

feldspar Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the ''plagioclase'' (sodium-calcium) feld ...

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay parti ...

and

iron oxides Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of whic ...

. The ratio of quartz to mica varies considerably. The stone can be split along mica-rich layers: it has a slaty cleavage and may therefore be called sandstone slate. Formerly riven (split with a chisel along the bedding planes between the sedimentary layers), it is now also often sawn. It is used for

flagstone Flagstone (flag) is a generic flat stone, sometimes cut in regular rectangular or square shape and usually used for paving slabs or walkways, patios, flooring, fences and roofing. It may be used for memorials, headstones, facades and other con ...

s and for building walls.Articles apparently produced by Dermot Kennedy at http://www.cbstonesales.co.uk/, and also published in 2011 on Ezinearticles.com: , , Known for its hard-wearing and durable qualities, Yorkstone has been used in a wide array of building, construction and landscaping applications around the world for many years. In Yorkshire, split stones called ''thackstone'' (Scots ''thack'', English ''

thatch Thatching is the craft of building a roof with dry vegetation such as straw, water reed, sedge (''Cladium mariscus''), rushes, heather, or palm branches, layering the vegetation so as to shed water away from the inner roof. Since the bulk o ...

'') were employed as roofing. The traditional London paving stone has been cut and pressed from quarries in

Holmfirth Holmfirth is a town in the Metropolitan Borough of Kirklees, West Yorkshire, England, on the A635 and A6024 in the Holme Valley, at the confluence of the River Holme and Ribble, south of Huddersfield and west of Barnsley. It mostly con ...

, West Yorkshire. Yorkshire Stone is most commonly used for paving and garden walls, but it is also a popular choice for new builds as well as home extensions and conversions due to its durability to harsh weather conditions. The colour of Yorkstone depends on the minerals within its makeup and differs throughout the quarries from which it is mined. It also depends on the age of the stone and turns darker with weathering. Reused Yorkstone paving, salvaged from demolished sites, is valued for its naturally weathered surfaces. Reclaimed Yorkshire stone is popular for its colouring and for environmentally friendly builds. Yorkstone often shows features such as laminations with

cross bedding In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. The original ...

, and rusty Liesegang bands.

References

{{reflist Building stone Sandstone in the United Kingdom Mining in Yorkshire

See also

References