Porcellanite or porcelanite, is a hard, dense rock somewhat similar in appearance to unglazed porcelain. It is often an impure variety of chert containing clay and calcareous matter. [1] Porcellanite has been found, for example, in Northern Ireland, Poland and the Czech Republic. Porcellanite is also commonly found in the Northern Territory of Australia. There, it comes in a variety of colours, primarily white, yellow, red and purple.
At Tievebulliagh, Northern Ireland, porcellanite is a tough contact metamorphosed hornfels formed from a lateritic soil horizon within a basaltic intrusive/extrusive sequence. The rock is black to dark grey in colour. Tievebulliagh is the site of a Neolithic axe or stone tool quarry, and there is another quarry on Rathlin Island. [2] It is likely that roughouts or roughly-shaped prehistoric tools (celts) were chipped on site before transportation both within Ireland and over the Irish Sea to Britain.[ citation needed ] It is also likely that the final polish would have been performed near the site of use in cutting vegetation and trees.[ citation needed ] It was commonly polished on grooved blocks of hard sandstone.[ citation needed ]
Marble is a metamorphic rock consisting of carbonate minerals that recrystallize under the influence of heat, pressure and aqueous solutions, most commonly calcite (CaCO3) or dolomite and has a crystalline texture of varying thickness. Marble is typically not foliated (layered), although there are exceptions.
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Flint was widely used historically to make stone tools and start fires.
Soapstone is a talc-schist, which is a type of metamorphic rock. It is composed largely of the magnesium rich mineral talc. It is produced by dynamothermal metamorphism and metasomatism, which occur in the zones where tectonic plates are subducted, changing rocks by heat and pressure, with influx of fluids, but without melting. It has been a medium for carving for thousands of years.
A stone tool is, in the most general sense, any tool made either partially or entirely out of stone. Although stone tool-dependent societies and cultures still exist today, most stone tools are associated with prehistoric cultures that have become extinct. Archaeologists often study such prehistoric societies, and refer to the study of stone tools as lithic analysis. Ethnoarchaeology has been a valuable research field in order to further the understanding and cultural implications of stone tool use and manufacture.
Marble has been the preferred material for stone monumental sculpture since ancient times, with several advantages over its more common geological "parent" limestone, in particular the ability to absorb light a small distance into the surface before refracting it in subsurface scattering. This gives an attractive soft appearance that is especially good for representing human skin, which can also be polished.
Serpentine subgroup are greenish, brownish, or spotted minerals commonly found in serpentinite. They are used as a source of magnesium and asbestos, and as decorative stone. The name comes from the greenish colour and smooth or scaly appearance from the Latin serpentinus, meaning "serpent rock".
Dalkey is an affluent suburb of Dublin, and a seaside resort southeast of the city, and the town of Dún Laoghaire, in the county of Dún Laoghaire–Rathdown in the historic County Dublin, Ireland. It was founded as a Viking settlement and became an active port during the Middle Ages. According to chronicler John Clyn (c.1286–c.1349), it was one of the ports through which the plague entered Ireland in the mid-14th century. In modern times, Dalkey has become a seaside suburb that attracts some tourist visitors.
Quartzite is a hard, non-foliated metamorphic rock which was originally pure quartz sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals.
Penmaenmawr is a town and community in Conwy County Borough, Wales, which was formerly in the parish of Dwygyfylchi and the traditional county of Caernarfonshire. It is on the North Wales coast between Conwy and Llanfairfechan and was an important quarrying town, though quarrying is no longer a major employer. The population of the community was 4,353 in 2011, including Dwygyfylchi and Capelulo. The town itself having a population of 2,868 (2011).
Bluestone is a cultural or commercial name for a number of dimension or building stone varieties, including:
Catlinite, also called pipestone, is a type of argillite, usually brownish-red in color, which occurs in a matrix of Sioux Quartzite. Because it is fine-grained and easily worked, it is prized by Native Americans, primarily those of the Plains nations, for use in making ceremonial pipes, known as chanunpas or čhaŋnúŋpas in the Lakota language. Pipestone quarries are located and preserved in Pipestone National Monument outside Pipestone, Minnesota, in Pipestone County, Minnesota, and at the Pipestone River in Ontario, Canada.
Diabase, also called dolerite or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained to aphanitic chilled margins which may contain tachylite.
Beaghmore is a complex of early Bronze Age megalithic features, stone circles and cairns, 8.5 miles north west of Cookstown, County Tyrone in Northern Ireland, on the south-east edge of the Sperrin Mountains.
The mustard plant is any one of several plant species in the genera Brassica and Sinapis in the family Brassicaceae. Mustard seed is used as a spice. Grinding and mixing the seeds with water, vinegar, or other liquids creates the yellow condiment known as prepared mustard. The seeds can also be pressed to make mustard oil, and the edible leaves can be eaten as mustard greens. Many vegetables are cultivated varieties of mustard plants; domestication may have begun 6,000 years ago.
Tievebulliagh is a 402-metre-high (1,319 ft) mountain in the Glens of Antrim, Northern Ireland. It forms part of the watershed between Glenaan to the north and Glenballyemon to the south. It is situated about 4.4 km from Cushendall.
Carved stone balls are petrospheres dated from the late Neolithic, to possibly as late as the Iron Age, mainly found in Scotland, but also elsewhere in Britain and Ireland. They are usually round and rarely oval, and of fairly uniform size at around 2+3⁄4 inches or 7 cm across, with anything between 3 and 160 protruding knobs on the surface. They range from having no ornamentation to extensive and highly varied engraved patterns. A wide range of theories has been produced to explain their use or significance, with none gaining very wide acceptance.
A ceremonial pipe is a particular type of smoking pipe, used by a number of cultures of the indigenous peoples of the Americas in their sacred ceremonies. Traditionally they are used to offer prayers in a religious ceremony, to make a ceremonial commitment, or to seal a covenant or treaty. The pipe ceremony may be a component of a larger ceremony, or held as a sacred ceremony in and of itself. Indigenous peoples of the Americas who use ceremonial pipes have names for them in each culture's Indigenous language. Not all cultures have pipe traditions, and there is no single word for all ceremonial pipes across the hundreds of diverse Native American languages.
Forbes' Quarry is located on the northern face of the Rock of Gibraltar within the Upper Rock Nature Reserve in the British Overseas Territory of Gibraltar. The area was quarried during the 19th century to supply stone for reinforcing the fortress' military installations. In the course of the quarrying, a limestone cave was found. The second ever Neanderthal discovery was made within this cave when Cpt. Edmund Flint found the skull of an adult female Neanderthal in 1848.
The Ancestral Puebloans, also known as the Anasazi, were an ancient Native American culture that spanned the present-day Four Corners region of the United States, comprising southeastern Utah, northeastern Arizona, northwestern New Mexico, and southwestern Colorado. They are believed to have developed, at least in part, from the Oshara tradition, which developed from the Picosa culture. The people and their archaeological culture are often referred to as Anasazi, meaning "ancient enemies", as they were called by Navajo. Contemporary Puebloans object to the use of this term, with some viewing it as derogatory.
  | This article relating to archaeology in Northern Ireland is a stub. You can help Wikipedia by expanding it. |
 | This metamorphic rock-related article is a stub. You can help Wikipedia by expanding it. |