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/sidewalk chalk, and drywall. 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 translucent crystals of selenite. It also forms as an evaporite mineral and as a hydration product of anhydrite.
The Harz[haːɐ̯ts] is a Mittelgebirge that has the highest elevations in Northern Germany and its rugged terrain extends across parts of Lower Saxony, Saxony-Anhalt, and Thuringia. The name Harz derives from the Middle High German word Hardt or Hart, Latinized as Hercynia. The Brocken is the highest summit in the Harz with an elevation of 1,141.1 metres (3,744 ft) above sea level. The Wurmberg is the highest peak located entirely within the state of Lower Saxony.
Halle (Saale) is the largest city of the German state of Saxony-Anhalt, the fifth most populous city in the area of former East Germany after (East) Berlin, Leipzig, Dresden and Chemnitz, as well as the 31st largest city of Germany, and with around 239,000 inhabitants, it is slightly more populous than the state capital of Magdeburg. Together with Leipzig, the largest city of Saxony, Halle forms the polycentric Leipzig-Halle conurbation. Between the two cities, in Schkeuditz, lies Leipzig/Halle International Airport. The Leipzig-Halle conurbation is at the heart of the larger Central German Metropolitan Region.
Flossenbürg was a Nazi concentration camp built in May 1938 by the SS Main Economic and Administrative Office. Unlike other concentration camps, it was located in a remote area, in the Fichtel Mountains of Bavaria, adjacent to the town of Flossenbürg and near the German border with Czechoslovakia. The camp's initial purpose was to exploit the forced labor of prisoners for the production of granite for Nazi architecture. In 1943, the bulk of prisoners switched to producing Messerschmitt Bf 109 fighter planes and other armaments for Germany's war effort. Although originally intended for "criminal" and "asocial" prisoners, after Germany's invasion of the Soviet Union, the camp's numbers swelled with political prisoners from Eastern Europe. It also developed an extensive subcamp system that eventually outgrew the main camp.
Mauthausen was a Nazi concentration camp on a hill above the market town of Mauthausen, Upper Austria. It was the main camp of a group with nearly 100 further subcamps located throughout Austria and southern Germany. The three Gusen concentration camps in and around the village of St Georgen/Gusen, just a few kilometres from Mauthausen, held a significant proportion of prisoners within the camp complex, at times exceeding the number of prisoners at the Mauthausen main camp.
Mittelbau-Dora was a Nazi concentration camp located near Nordhausen in Thuringia, Germany. It was established in late summer 1943 as a subcamp of Buchenwald concentration camp, supplying slave labour from many Eastern countries occupied by Germany, for extending the nearby tunnels in the Kohnstein and for manufacturing the V-2 rocket and the V-1 flying bomb. In the summer of 1944, Mittelbau became an independent concentration camp with numerous subcamps of its own. In 1945, most of the surviving inmates were evacuated by the SS. On 11 April 1945, US troops freed the remaining prisoners.
Selenite, also known as satin spar, desert rose, or gypsum flower are four crystal structure varieties of the mineral gypsum. These four varieties of gypsum may be grouped together and called selenite.
Natzwiller is a commune in the Bas-Rhin department in Grand Est in northeastern France.
The Jeita Grotto is a system of two separate, but interconnected, karstic limestone caves spanning an overall length of nearly 9 kilometres (5.6 mi). The caves are situated in the Nahr al-Kalb valley within the locality of Jeita, 18 kilometres (11 mi) north of the Lebanese capital Beirut. Though inhabited in prehistoric times, the lower cave was not rediscovered until 1836 by Reverend William Thomson; it can only be visited by boat since it channels an underground river that provides fresh drinking water to more than a million Lebanese.
Blankenburg (Harz) is a town and health resort in the district of Harz, in Saxony-Anhalt, Germany, at the north foot of the Harz Mountains, 12 miles (19 km) southwest of Halberstadt.
Monowitz was a Nazi concentration camp and labor camp (Arbeitslager) run by Nazi Germany in occupied Poland from 1942–1945, during World War II and the Holocaust. For most of its existence, Monowitz was a subcamp of the Auschwitz concentration camp; from November 1943 it and other Nazi subcamps in the area were jointly known as "Auschwitz III-subcamps". In November 1944 the Germans renamed it Monowitz concentration camp, after the village of Monowice where it was built, in the annexed portion of Poland. SS Hauptsturmführer (Captain) Heinrich Schwarz was commandant from November 1943 to January 1945.
Arbeitslager is a German language word which means labor camp. Under Nazism, the German government used forced labor extensively, starting in the 1930s but most especially during World War II. Another term was Zwangsarbeitslager.
The Kohnstein is a hill in Thuringia, Germany, 2 kilometres southwest of the village of Niedersachswerfen and 3 kilometres northwest of the centre of the town of Nordhausen. Gypsum mining created tunnels in the hill that were later used as a fuel/chemical depot and for Nazi Germany factories, including the Mittelwerk V-2 rocket factory that used Mittelbau-Dora slave labour.
The Valentin submarine factory is a protective shelter on the Weser River at the Bremen suburb of Rekum, built to construct German U-boats during World War II. The factory was under construction from 1943 to March 1945 using forced labour, but was damaged by air-raids and unfinished by the end of the war. The Valentin factory was the largest fortified U-boat facility in Germany, and was second only to those built at Brest in France.
Hinterbrühl is a town in the district of Mödling in the Austrian state of Lower Austria. It is home to the Seegrotte, a system of caves including Europe's largest underground lake. During World War II, a satellite camp of Mauthausen concentration camp was opened inside the caverns, producing parts for the He 162 jet fighter.
Kaufering was a system of eleven subcamps of the Dachau concentration camp located around the town of Landsberg am Lech in Bavaria, which operated between 18 June 1944 and 27 April 1945. Previously, Nazi Germany had deported all Jews from the Reich, but having exhausted other sources of labor, Jews were deported to Kaufering to create three massive underground bunkers, Weingut II, Diana II, and Walnuss II, which would not be vulnerable to the Allied bombing which had devastated German aircraft factories. The bunkers were intended for the production of Messerschmitt Me 262 aircraft, but none were produced at the camps before the United States Army liberated the area.
Riese is the code name for a construction project of Nazi Germany in 1943–1945, consisting of seven underground structures located in the Owl Mountains and Książ Castle in Lower Silesia, at the time part of Germany and now located within the territory of Poland.
The Unicorn Cave is the largest show cave in the West Harz, about 1½ kilometres northwest of Scharzfeld in the borough of Herzberg am Harz in central Germany. It is a karst cave developed in dolomite strata that is part of the Zechstein.
The Barbarossa Cave is an anhydrite cave in the Kyffhäuser Hills near Rottleben in the east German state of Thuringia. It is a cave with large caverns, grottos and lakes. The anhydrite has formed gypsum on the surface due to the air moisture in the cave and, as a result, has increased in volume. The resulting layers of gypsum gradually separate from the underlying rock and hang like wallpaper from the walls and ceilings of the caverns.
Leitmeritz was the largest subcamp of the Flossenbürg concentration camp, operated by Nazi Germany in Leitmeritz, Reichsgau Sudetenland. Established on 24 March 1944 as part of an effort to disperse and increase war production, its prisoners were forced to work in the caverns Richard I and II, producing Maybach HL230 tank engines for Auto Union and preparing the second site for intended production of tungsten and molybdenum wire and sheet metal by Osram. Of the 18,000 prisoners who passed through the camp, about 4,500 died due to disease, malnutrition, and accidents caused by the disregard for safety by the SS staff who administered the camp. In the last weeks of the war, the camp became a hub for death marches. The camp operated until 8 May 1945, when it was dissolved by the German surrender.
