Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard chalk and wallboard. A massive fine-grained white or lightly tinted variety of gypsum, called alabaster, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire and the Nottingham alabasters of Medieval England. Gypsum also crystallizes as beautiful translucent crystals of selenite (mineral). It also forms as an evaporite mineral and as a hydration product of anhydrite.
Wookey Hole Caves are a series of limestone caverns, a show cave and tourist attraction in the village of Wookey Hole on the southern edge of the Mendip Hills near Wells in Somerset, England. The River Axe flows through the cave. It is a Site of Special Scientific Interest (SSSI) for both biological and geological reasons. Wookey Hole cave is a "solutional cave", one that is formed by a process of weathering in which the natural acid in groundwater dissolves the rocks. Some water originates as rain that flows into streams on impervious rocks on the plateau before sinking at the limestone boundary into cave systems such as Swildon's Hole, Eastwater Cavern and St Cuthbert's Swallet; the rest is rain that percolates directly through the limestone. The temperature in the caves is a constant 11 °C (52 °F).
Geodes are geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely circular rocks, in which masses of mineral matter are secluded. The crystals are formed by the filling of vesicles in volcanic and sub-volcanic rocks by minerals deposited from hydrothermal fluids; or by the dissolution of syn-genetic concretions and partial filling by the same, or other minerals precipitated from water, groundwater or hydrothermal fluids.
Desert rose is the colloquial name given to rose-like formations of crystal clusters of gypsum or baryte which include abundant sand grains. The 'petals' are crystals flattened on the c crystallographic axis, fanning open in radiating flattened crystal clusters.
Alabaster Caverns State Park is a 200-acre (0.81 km2) state park approximately 4.5 miles (7.2 km) south of Freedom, Oklahoma, United States near Oklahoma State Highway 50. The park attracted 24,706 visitors in FY 2016, The lowest count of the three parks in its part of Oklahoma. According to the Encyclopedia of Oklahoma History and Culture, the park Previously attracted about 40,000 visitors per year. It is home to the largest natural gypsum cave in the world that is open to the public. The gypsum is mostly in the form of alabaster. There are several types of alabaster found at the site, including pink, white, and the rare black alabaster. This black alabaster can be found in only three veins in the world, one each in Oklahoma, Italy and China. Another form of gypsum can be found in the many selenite crystal formations.
At 138.3 miles (222.6 km), Lechuguilla Cave is the eighth-longest explored cave in the world and the second deepest in the continental United States. It is most famous for its unusual geology, rare formations, and pristine condition.
Peñoles is a subsidiary company owned by Grupo BAL. Peñoles is the second largest Mexican mining company, the first Mexican producer of gold, zinc and lead and the world leader in silver production. Peñoles is a company with active mines within Mexico and with some prospection projects in South America. Holdings includes the Fresnillo Silver Mine / Mina Proaño, the Met-Mex Peñoles metallurgical complex and Química del Rey; a Chemical facility; three operations. Peñoles produces about 80,500,000 troy ounces (2,500,000 kg) of silver and 756,100 troy ounces (23,520 kg) of gold annually. Other metals that the company produces are zinc, lead, copper, bismuth, and cadmium.
Treak Cliff Cavern is a show cave near Castleton in Derbyshire, England. It is part of the Castleton Site of Special Scientific Interest and one of only two sites where the ornamental mineral Blue John is still excavated. As part of an agreement with English Nature, the Blue John that can be seen in the show cave is not mined but it is extracted in small quantities from other areas of the cave and made into saleable items like bowls, jewellery and ornaments.
Sarawak Chamber is the largest known cave chamber in the world by area and the second largest by volume after the Miao Room in China. It is in Gua Nasib Bagus, which is located in Gunung Mulu National Park, in the Malaysian state of Sarawak on the island of Borneo.
Cumberland Caverns is a national natural landmark and show cave located in McMinnville. It is the second longest cave in Tennessee and makes the list of longest caves in the United States and in the world.
Pen Park Hole is a large cavern situated underground, at the edge of Filton Golf Course. The cavern was discovered accidentally in the 17th Century and the first descent was made by Captain Sturmy in 1669. The entrance is adjacent to the Southmead and Brentry housing estates of north Bristol. Access is tightly controlled by Bristol City Council. It was scheduled as a Site of Special Scientific Interest in August 2016 on account of its geological origins, and its cave invertebrate community including the cave shrimp Niphargus kochianus, which is normally known as a spring seepage or chalk aquifer species.
Lamb Leer is a 14.59 hectare geological Site of Special Scientific Interest between East Harptree and Priddy in the Mendip Hills, Somerset, notified in 1983. The cavern is a fragment of a very ancient major cave system which now contains one of the largest chambers in the Mendip Hills.
Titan is a natural cavern near Castleton in the Derbyshire Peak District, and is the deepest shaft of any known cave in Britain, at 141.5 metres (464 ft). The existence of Titan was revealed in November 2006, following its discovery on 1 January 1999 after cavers discovered connections from the James Hall Over Engine Mine to both Speedwell Cavern and Peak Cavern. Previously, the deepest known underground shaft in Britain had been Gaping Gill on the slopes of Ingleborough in the Yorkshire Dales.
Oxlow Cavern is a part-natural and part-mined cavern near Castleton in Derbyshire, England. It is situated on the south side of the road running from the A623 at Sparrowpit to the Winnats Pass, west of Castleton, and is almost opposite Giant's Hole on the other side of the road. A few yards from Oxlow Cavern is the connecting Maskill Mine.
Carlsbad Caverns National Park is an American national park in the Guadalupe Mountains of southeastern New Mexico. The primary attraction of the park is the show cave, Carlsbad Cavern. Visitors to the cave can hike in on their own via the natural entrance or take an elevator from the visitor center.
Naica is a town in the Mexican state of Chihuahua. It is located in the municipality of Saucillo. As of 2010, the town of Naica had a population of 4,938, up from 4,775 in the 2005 INEGI Census.
Cave of the Crystals or Giant Crystal Cave is a cave connected to the Naica Mine at a depth of 300 metres (980 ft), in Naica, Chihuahua, Mexico.
Gruta de Maquiné (MG-0243), also Lapa Nova de Maquiné, is the oldest and one of the most commercially visited caves in Brazil. It is located about 5 km (3.1 mi) from Cordisburgo and 143 km (88.9 mi) northwest of Belo Horizonte, in the State of Minas Gerais. The cave has seven huge chambers explored, amounting to 650 m (2,130 ft) (linear) and unevenness of the ground of only 18 m (59 ft). Safety measures like lighting, walkways and handrails allow a multitude of visitors to enjoy safely the wonders of the grotto where the whole journey is accompanied by an experienced local guide.