Because its refractive index approximates that of water, transparent, colorless cryolite becomes almost invisible when placed in water. Also present in this pegmatite are argentiferous galena, sphalerite, fluorite, chalcopyrite, pyrite and, most notably, well-developed, reddish-brown crystals of siderite. After studying specimens collected at Ivittuut, the Danish physician Peder Christian Abildgaard described and named cryolite in Mining began at Ivittuut in , with cryolite first used as a minor source of aluminum, then as a raw material for manufacturing caustic soda sodium hydroxide.
Metallurgists of the mids realized that strong, lightweight aluminum had enormous industrial potential. But the metal could only be extracted in small amounts from cryolite and several other rare minerals.
Although aluminum was present in huge quantities in alumina aluminum oxide in abundant bauxite-type deposits, it could not be economically separated. But in , American and French chemists learned to dissolve alumina in molten cryolite, then to inexpensively extract metallic aluminum by electrolysis. It also sharply boosted demand for cryolite which, for the next 50 years, was critical in the development of the modern aluminum industry.
By , the Ivittuut mine consisted of a steadily expanding open pit, living quarters, machine shops, loading docks, a medical clinic, and a man crew. Because the Greenland climate limited mining to summer, miners flooded the pit with seawater in autumn to prevent it from filling with snow. Each spring, they would break the ice and pump the water out. The town has a power station with fuel supplies to service this station and local traffic and to support mineral exploration. About 5.
This is a global leap forward for the company to expand its interests with unique opportunities in the green energy metals and minerals sector. EPM is now well positioned not only to deliver increasing value for our shareholders by being able to achieve cost effective results from assay of the 19, m of drill core presently in storage but also delineating short term opportunities in the highly sought after REE sector. In the short run, having substantial high purity quartz silica still within the pit area puts the company in a position to potentially be a near term supplier to the electronic, solar, optical and silicon metal industry.
High purity quartz is a highly sought after industrial mineral. This deposit could provide an ideal product for neutralising acid mine and process water produced by other miners in the Greenlandic region. During World War 2, when Germany occupied Denmark, the Allies sent a platoon to Ivittuut to protect the mine from the Nazis because of its importance in airplane production.
To strengthen its hold, the US Navy built a naval base three miles away in Kangilinnguit, and the US Coast Guard built a base across the fjord from Ivittuut, holding hundreds more soldiers. To protect its location, no photographs of Ivittuut were allowed to be taken during the war, and no one was allowed to write letters to family or friends for fear that the Germans would intercept them.
After the war, Denmark continued to mine cryolite until the mines were exhausted in the late s. The mine closed in The cryolite quarry at Ivittuut. Image credit: Mindat. Greenland Landmarks mines. More on Amusing Planet.
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