Millstone Grit is any of a number of coarse-grained sandstones of Carboniferous age which occur in the British Isles . The name derives from its use in earlier times as a source of millstones for use principally in watermills . Geologists refer to the whole suite of rocks that encompass the individual limestone beds and the intervening mudstones as the Millstone Grit Group . The term Millstone Grit Series was formerly used to refer to the rocks now included within the Millstone Grit Group together with the underlying Edale Shale Group .
53-565: The term gritstone describes any sandstone composed of coarse angular grains, and specifically refers to such sandstones within the Pennines and neighbouring areas of Northern England. Rocks assigned to the Millstone Grit Group occur over a wide area of Northern England, where they are a hugely important landscape-forming element of the rock succession. They also occur in parts of northeast Wales and northwest Ireland . The group comprises
106-613: A Leat rather than a canal . After the ironstone melted, the Pig iron was brought to Drumshanbo Finery forge to the south of Lough Allen to produce the malleable iron product which was transported to Dublin and Limerick by boat. Folklore claims the " Iron ore was conveyed to the Drumshanbo furnaces by boat, on Lough Allen. The sources of supply, were, the Slieven an Iern [Anerin], Ballinaglera, Arigna mountains, all situated around Lough Allen. It
159-417: A "remarkable extent" of Namurian marine fauna bands, abundant with goniatite - Bivalvia , at Sliabh an Iarainn. She described some rock layers as particularly fossiliferous, the shale bands abundant with goniatite faunas and Bivalvia marine and freshwater molluscs. The unfossiliferous shales often contain numerous clay-ironstone bands making conditions intolerable for marine organisms. At most of
212-584: A claim echoed by a 19th-century survey of County Leitrim – " A hundred years ago almost the whole country was one continued, undivided forest, so that from Drumshanbo to Drumkeeran, a distance of nine or ten miles, one could travel the whole way from tree to tree by branches ". These great forests in Leitrim and on the west side of Lough Allen were denuded for the making for Charcoal for Iron works around Sliabh an Iarainn. Immense piles of cleared timber existed at Drumshanbo in 1782. The Book of Invasions describes
265-576: A goddess, and Dagna the goddess mother. Messengers informed Eochaid son of Ere, and king of the Fir Bolg , that a new race of people had settled in Ireland. The Firbolgs sent forward their champion Sreng and the Tuatha De Danann getting sight of his approach sent their champion Bres . The two champions had a meeting at Magh Rein below Sliabh an Iarainn but no peace was concluded. The Tuatha Dé Danann defeated
318-561: A succession of sandstones, mudstones and siltstones , the specifics of the sequence varying from one area to another. They give rise both to a number of escarpments , known locally as edges , and a series of high plateaux throughout the region, many of which are of considerable cultural significance. They are the major landscape-forming rocks of the northern part of the Peak District (the Dark Peak ) and of its eastern and western flanks in
371-419: Is a hard, coarse-grained, siliceous sandstone . This term is especially applied to such sandstones that are quarried for building material . British gritstone was used for millstones to mill flour, to grind wood into pulp for paper and for grindstones to sharpen blades. "Grit" is often applied to sandstones composed of angular sand grains. It may commonly contain small pebbles . " Millstone Grit "
424-543: Is a literary initiative started in 2004 to write about the history of the people who inhabited the necklace of townlands on the flanks of Sliabh-an-Iarainn and Ben Croy, in County Leitrim. The goal was to preserve a memory of the Ultachs, Catholic refugees displaced out of Ulster in 1795 who made a home on the mountain, their experiences of famine and emigration, and the resilience of the remaining communities. This social history
477-549: Is a mountain in County Leitrim , Ireland . It rises to 585 metres (1,919 ft) and lies east of Lough Allen and northeast of Drumshanbo . It is part of the Cuilcagh Mountains . The mountain was shaped by the southwestward movement of ice age glaciers over millions of years, the morainic drift heaping thousands of drumlins in the surrounding lowlands. Historically there were many iron ore deposits and ironworks in
530-519: Is a thick obscuring mantle of peat bog and glacial drift below the steep grit slope, with heather and peat bog forming a thick mantle over most of the upland plateau at the summit. Rocks are typically horizontal or gently dipping, except in land-slipped areas. Impressive landslides have occurred along the western face, and at the south-western and south-eastern corners of the mountain, indicating an appreciative magnitude of land-slipping. The geological section from Lough Allen across Sliabh an Iarainn has
583-425: Is also traceable for 0.8 kilometres (0.5 mi) along the south-eastern slopes of Bencroy. More than two coal seams may be present at Sliabh an Iarainn, though the only rocks observable over the coal seams (in the millstone grit ) are the lower coal measure containing black and brown splintery shales of a considerable thickness at Bencroy to the east and Barnameenagh to the west. The Sliabh an Iarainn project
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#1732844614433636-677: Is also used as aggregate in path and road construction. The gritstone edges of West Yorkshire and the Peak District provide one of the classic areas in Britain for rock climbing. Public access to these edges for climbing developed at much the same time as access for walkers to the moors of the Pennines was established during the first half of the twentieth century. Their proximity to large centres of population resulted in their rapid development as climbing venues. Gritstone Gritstone or grit
689-489: Is an informal term for a succession of gritstones which are to be found in the Pennines (including the Peak District ) of northern England. These sediments were laid down in the late (upper) Paleozoic era, in the Carboniferous period, in deltaic conditions. The Millstone Grit Group is a formal stratigraphic term for this sequence of rocks. The gritstone edges of the Peak District are an important climbing area and
742-590: Is considered important, being housed at the Murchison Museum, Imperial College, British Geological Survey Museum, and the Natural Museum in London. Sliabh an Iarainn is an imposing hill, towering over and dominating the rugged landscape. It rises from the eastern shore of Lough Allen to a summit elevation of 586-metre (1,923 ft). On this summit at 520 metres (1,706.0 ft), a Triangulation station of
795-484: Is the most eastern part of the Connacht coal field. Well-marked escarpment lines are visible, partly exposed by lines of geological fault on all sides of the mountain valleys, the collapsed layers removed by denudation . The outcrop of two coal seams, crow coals with a sandstone roof and middle coal under a slate roof, are traceable some difficulty along the grit escarpment on the western side of Sliabh an Iarainn towards
848-601: Is thought that the town of Drumshanbo had its origin in these industries ". Drumshanbo Iron works closed in 1765. Ballinamore Iron works was established sometime after 1693 and continued production until probably 1747 when the business was put up for sale, the assets including a furnace, forge, slitting mill, mine yards, coal yards, large quantities of pig iron , mine and coals. The last Iron works in Ireland, located at Creevelea in County Leitrim, closed around 1770 though they reopened again years later again. Crevelea works ceased production in 1858, and later attempts to revive
901-454: The Belcoo area, to the north of which it widens before rapidly narrowing towards Lough Erne . Sliabh an Iarainn, at the southern end of this mass, and east of Lough Allen, is a flat topped mountain with a prominent and steep grit slope, easily mistaken for the summit from a distance, when in fact another 50 metres (164.0 ft) of shales form a small residual outlier overlying this grit. There
954-618: The English Midlands and East Anglia to the continent and is now known as the Wales-Brabant High , though was formerly referred to as St George's Land. Other uplands the erosion of which would provide the source material for the Millstone Grit lay to the north and northeast of the region. The Pennine Basin received input of sand and mud largely from southerly directed rivers from these northern landmasses. Rivers running north off
1007-531: The Ordnance Survey is fixed on a low concrete plinth. It is part of the Cuilcagh Mountains, which stretch from Sliabh an Iarainn to Cuilcagh . Sliabh an Iarainn is composed of Carboniferous shales , and sandstones blanketed by heather-covered moorland, and located in an area of Upper Carboniferous rocks extending from the northern extremity of Lough Erne for about 48 kilometres (29.8 mi) to
1060-660: The Silesian (series) . The Geological survey of Ireland (1878) wrote " the Geologist may examine all the formations of the district from the Lower Silurian up to the outlier of Coal-measures that crowns Slieve-an-Ierin… It is a rare thing in most countries to find so much comprised in so small a space ". In her landmark study "The Palaeontology of the Namurian rocks of Slieve Anierin, Co. Leitrim, Eire", Patricia Yates (1962) demonstrated
1113-569: The Tuatha Dé Danann , tribe of the goddess Danu arriving in Mesolithic Ireland through the air before landing their floating-ships on the summit of Sliabh an Iarainn, " the mountain of Conmaicne Rein in Connacht ". The men included Nuada the king, Manannan the powerful, Neit the battle god, and Goibniu the Smith. The women included Badb the battle goddess, Eadon the poets nurse, Brigit
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#17328446144331166-587: The Yorkshire Dales they cover the south-east edge, but north of the Craven Faults , due to weathering , they form only cappings to separate hills. A small area of Millstone Grit Group rocks stretches through Flintshire and Wrexham into the northwest corner of Shropshire near Oswestry . The term "Millstone Grit" was also adopted in South Wales where rocks of similar age and lithology are found though
1219-590: The counties of Derbyshire , Staffordshire and Cheshire . The great expanses of moorland around Bleaklow and Black Hill and fringed with broken outcrops of gritstone are characteristic of the area. The ‘eastern edges of the Peak District’ comprise a broadly north-south arranged series of west-facing cliffs from Bamford Edge in the north through Stanage Edge , Burbage Edge , Froggatt Edge , Curbar Edge , Baslow Edge , Gardom's Edge , Birchen Edge , Dobb/Chatsworth Edge , Harland Edge and Fallinge Edge in
1272-776: The 1600s, the Ore rather tough like Spanish Iron. Commercial Iron works existed around Sliabh an Iarainn c. 1630 , and though nearly all were destroyed during the Irish Rebellion of 1641 , they were revived after the Irish Confederate Wars at the earliest, or in the 1690s after the Battle of the Boyne. Many smelting works employed English or other foreigners instead of Irish labour which generated much local hostility. The siting of Smelting works contiguous to Lough Allen allowed for
1325-835: The Firbolg at Battle of Moytura . Three centuries later the De Danann retreated to the Celtic Otherworld on being displaced by the Milesians , mythological ancestors of the Irish race. For there by old tradition the Tuatha de Danann had first descended from heaven, giving to Sliab in larainn its peculiar sanctity. Among the old races skilled craftsmen, as we may still see in the Dublin Museum, proved their talent. Alice Stopford Green, History of
1378-635: The Irish State to 1014 . Metal workers were held in high esteem, and the Irish Pantheon Gobán Saor is synonymous with the legendary Scandinavian named Vaeland Smith and Goibniu of the Tuatha De Dannan. According to oral tradition, Gobán Saor ("Goibhenen"), Tuatha De Danann metalsmith , worked the mines here. Some fringe historians suggest a passage in the Book of Invasions concerning
1431-697: The Millstone Grit Series of this region has recently been formally renamed by the British Geological Survey as the Marros Group . The thickest bed of sandstone within it was known as the Basal Grit and this has now been renamed as the Twrch Sandstone. The Farewell Rock was formerly considered to be the uppermost unit of the Millstone Grit series of South Wales though it is now included within
1484-608: The Namurian, the Yeadonian includes the Lower Haslingden Flags and the last sandstone in the entire Millstone Grit succession known as the Rough Rock . It is a widespread unit which attains a thickness of around 45m though is more generally 15m thick. Various of the sandstone beds of the Millstone Grit have been quarried for building stone, paving flags and roofing material. Its use in the construction of dry stone walls across
1537-713: The Ordnance and Caulfield had the sale confirmed by letters patent of 12 July 1620 (Pat. 19 James I. XI. 45 Slewnerin ). In the remote mountainous Cuilcagh -Anierin uplands, an oligotrophic lake called "Lough Munter Eolas" is named after Eolais Mac Biobhsach and the Muintir Eolais , the most famous of the Leitrim sub-septs of the Conmaicne Rein). This lake straddles the border of Moneensauran townland in west County Cavan and Slievenakilla townland in south County Leitrim. Iron Ore has been dug at Sliabh an Iarainn since
1590-489: The Stony River valley, becoming completely obscured by drift deposits on the southern flanks, and on the eastern flanks to a mile North of Lough Nabellbeg continuing through the townlands of Sradrinagh and Cornamucklagh South obscured by a thick blanket of peat bog, becoming visible again further north on the western side of the hill at Cleighran More and Cleighran Beg where faults are evident. The outcrop of both coal seams
1643-704: The Wales-Brabant High deposited material in the southern parts of the Pennine basin from northeast Wales to the Peak District. Southerly flowing rivers from this same landmass were responsible for the Millstone Grit/Marros Group succession in South Wales. During much of the Carboniferous Period, world sea-levels were fluctuating in response to the growth and decline of a series of major ice-caps over
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1696-411: The appearance of the Tuatha Dé Danann in Ireland, records " the arrival of aliens in spacecraft with cloaking devices " at Sliabh an Iarainn. In the parish of Kiltubrid the term fear gorta (Irish for "hungry man") refers to a hunger which may supposedly afflict a person on the mountains, proving fatal if not quickly satisfied. This hunger is said to immediately seize any person who walks on
1749-723: The area has been adopted as the emblem of the Peak District National Park. As an image, the millstone is widely visible on literature but use is made of the objects themselves at many of the entrances to the National Park. These rocks extend northwards through the South Pennines of Lancashire and West Yorkshire and westwards into the Forest of Rossendale and West Pennines and the Forest of Bowland , also in Lancashire. At
1802-462: The area. Irish mythology associates the mountain with the Tuatha Dé Danann , particularly the smith god Goibniu . Sliabh an Iarainn is an important natural heritage site with exposed marine and coastal fauna of paleontological interest The name Sliabh an Iarainn means "mountain or moor of the iron" and refers to the many iron ore deposits in the area. Boate (1652) said "the mountains are so full of this metal, that hereof it hath got in Irish
1855-403: The areas where it outcrops is considerable. In neighbouring limestone areas, gritstone has often been preferred in the past for use as gateposts and lintels. The very name of the rock derives from its widespread use within cornmills where it proved suitable for grinding stones. It also found agricultural use as drinking troughs for animals. The majority of the quarrying for such use took place along
1908-672: The continents then clustered around the South Pole . Britain lay in the equatorial region. At times of high sea-level, silt and mud accumulated within the Pennine basin whilst at times of low sea-level, major deltas prograded across the region, their legacy being the thick sandstone beds of the Millstone Grit Group. The Millstone Grit Group comprises over thirty individually named sandstones, some of regional extent, others more local in their occurrence. The intervening mudstones and siltstones are not generally named though important marine bands within them are named. The oldest, and hence lowermost in
1961-477: The east side of Lough Allen. The site of the furnace can still be pointed out, and the field in which it is situated has got the name of the Furnace Meadow ". Cornashameogue is overlooked by the adjacent townland of Irish : Barnameenagh West , meaning 'top of the mines'. Local folklore recalls a so-called "Sliabh an Iarainn canal" connected with Cornashamsoge smelting works- " the ore had to be conveyed to
2014-434: The eastern edges of the Peak District. Millstone Edge was a significant source whilst abandoned millstones can be seen below the edges at Stanage, Froggatt and Baslow. Bramley Fall stone is a notable type of Millstone Grit sourced from around the village of Bramley, near Leeds. Some of the sandstones serve as aquifers into which numerous wells and boreholes have been sunk to provide local water supplies. Crushed gritstone
2067-737: The following Arnsbergian sub-stage. The Kinderscoutian includes the Kinder Grit, Longnor Sandstones, Shale Grit, Todmorden Grit, Parsonage Sandstone, Heysham Harbour Sandstone, Eldroth Grit and Ellel Crag Sandstone. The next sub-stage of the Namurian succession is the Marsdenian and it is to this that the Chatsworth Grit , Huddersfield White Rock, Holcombe Brook Grit, Greta Grits, Roaches Grit , Ashover Grit , Gorpley Grit, Pule Hill Grit, Fletcher Bank Grit, Brooksbottom Grit, Five Clouds Sandstones and Sheen Sandstones are assigned. The closing sub-stage of
2120-533: The following general succession of strata - The so-called "Yoredale beds" extend down to the edge of Lough Allen on the west, and to the top of the Carboniferous Limestone on the south and south-east. At the base of the succession occur limestones, calcareous mudstones, and sandstones, but from the base of the Namurian upwards shales are continuous until the millstone grit horizon. Sliabh an Iarainn
2173-604: The fossiliferous levels in the Namurian beds the number of goniatites and Bivalvia are usually very high with the diversity of species low. The richest and most diverse band in the succession at Sliabh an Iarainn, in terms of species present, contains Trilobites , brachiopods , gastropods , echinoids and Bryozoa . Fragments of trilobites occur abundantly at particular bands. Overall, Yates documented nearly 120 distinct fossiliferous sites around Sliabh an Iarainn, her work complemented by extensive photographs of often beautifully preserved fossils. Her study of Sliabh an Iarainn
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2226-418: The furnace for a distance of about 3 miles. For this purpose a canal was made. The canal ran by the foot of the mountain. Several rivers flow westward from the mountain into Lough Allen. The largest of these is the stoney river, a river that becomes a roaring torrent in times of heavy rain, often overflowing its banks, and causing great destruction, to lands, crops and houses. Build the time mentioned above, about
2279-470: The industry here complete failures. There was an Iron works at Swanlinbar in County Cavan, right at the far north-east corner of Sliabh an Iarainn, though it had closed by 1785 according to an observer who wrote- " The furnaces of Ireland were never so forsaken and deplorable a way as they are at present... The great iron-works which were at Swanlinbar ... are abandoned ". In 1962, an attempt to mine
2332-574: The lower 1.1 metres (3 ft 7.3 in) thick coal-seam located about 366 metres (1,200.8 ft) west of the Rocking Stone (" Fionn MacCumhaill ’s Rock") was abandoned, the coal being poor quality and seams non persistent. On the eastern side of Sliabh an Iarainn there is another abandoned level in the upper seam which is 0.3 metres (11.8 in) thick, the location possibly being above Aughacashel House. Long ago Ireland had been covered in Woodland,
2385-545: The name of Slew Neren, that is, Mountains of Iron". It is sometimes anglicized 'Slieve Anierin' or 'Slievanierin'. The mountain was anciently named Sliab Comaicne , or the "mountain of the Conmaicne Rein in Connacht". Sliabh an Iarainn is an important natural heritage site due to unbroken sequence of Carboniferous marine fossils present in the rock layers spanning the Namurian (326-315 million years ago) and lower Westphalian (313-304 million years ago) stages of
2438-638: The overlying South Wales Coal Measures . The term has also been adopted at Slieve Anierin in northwest Ireland, describing the series of shales, grits, and coal seams, occurring from the base of the Namurian upwards. The Millstone Grit dates to the Namurian Stage of the Carboniferous Period . At this time a series of isolated uplands existed across the British Isles region. One particular east-west aligned landmass stretched from Wales through
2491-510: The rock is much relished by English climbers , among whom it has almost cult status and is often referred to as "God's own rock". The rough surface provides outstanding friction, enabling climbers to stand on or grip the subtlest of features in the rock. This article related to petrology is a stub . You can help Misplaced Pages by expanding it . Slieve Anierin Sliabh an Iarainn ( Irish for "iron mountain"), anglicized Slieve Anierin ,
2544-558: The south. To the east of these edges is a broad band of relatively flat moorland known as the Eastern Moors. Towards the western margins of the Peak District are a rather more broken series of edges, facing in a variety of directions, from those surrounding the high plateaux of Kinder Scout and Combs Moss to the imposing crags of the Roaches , Hen Cloud and Ramshaw Rocks in the south. A millstone shaped from Millstone Grit quarried in
2597-486: The southern tip of Lough Allen. Shale is the dominant rock type throughout the Carboniferous succession, but a thick grit, with coal seams, occurs in the lower rock layers of 326-315 million years ago . At its greatest width the outcrop stretches eastwards towards Swanlinbar 32 kilometres (19.9 mi) distant. The outcrop narrows northwards, interrupted by a deep shoreline indentation of Carboniferous Limestone around
2650-507: The succession is the thick Pendle Grit of central Lancashire. It is succeeded by the sandstone known variously as the Brennand Grit, Warley Wise Grit and Grassington Grit. These are all of Pendleian (E1) age – the lowermost sub-stage of the Namurian. The Lower Follifoot Grit, Silver Hills Sandstone, Nottage Crag Grit, Marchup Grit, Red Scar Grit, Ward’s Stone Sandstone, Cocklett Scar Sandstones and Dure Clough Sandstones are all assigned to
2703-466: The transportation of Pig Iron in boats of up to forty tons. Commercial iron mining declined after c. 1750 – c. 1760 as deforestation exhausted the fuel for burning charcoal. In the 17th century the Cornashamsoge smelting works founded. Local tradition says " about the year 1650, there was a furnace for smelting Iron ore in the downland of Cornashameogue, situated on
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#17328446144332756-498: The year 1650. The water of the stoney river was diverted into the canal. The canal then was fed principally by this river, and in a lesser degree by the other smaller rivers that ran in the same direction. All the rivers ran at right angles to the canal. The water also supplied the power that worked the furnace. As to the Slieve an Iren [Anerin] canal, there are but very meagre traces of it at the present time ". His description best describes
2809-413: Was released in three volumes- In the 1609 Plantation of Ulster , Sliabh an Iarainn formed part of lands which were granted to John Sandford of Castle Doe , County Donegal (the father-in-law of Thomas Guyllym of Ballyconnell ) by letters patent dated 7 July 1613 (Pat. 11 James I – LXXI – 38, Slewenerin ). It was later sold by Sandford to his wife's uncle Toby Caulfeild, 1st Baron Caulfeild , Master of
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