Minerals in Greenland
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GO_12.qxp:GO-02 copy.qxp 12/02/08 10:58 Side 1 Minerals in Greenland No. 12 - February 2008 GO_12.qxp:GO-02 copy.qxp 12/02/08 10:59 Side 2 Minerals in Greenland Minerals are an integrated part of the geological history. The variation and wealth of minerals in Greenland have been significant in rendering the country with its prominent place on the geological world map, shared with only very few other regions. In their widest context, minerals under- standably attracted a great deal of attention from the first explorations in the early 1800s. Introduction Minerals and mineral resources have been identified as a cornerstone of Greenland’s economical development. Therefore many initiatives have been implemented to accel- Slab of basalt from Disko in West Greenland studded with grains and crystals of metallic iron. Field of view: 20 x 24 cm. erate the establishment of the mineral in- dustry. After 150 years of almost continu- Giesecke travelled by umiaq - an open Inuit ous mining, and following a brief break skin boat - in South and West Greenland since 1990, Greenland now seems to be from 1806-13. Several mineralogical records entering a new phase of mineral exploita- were made during this long period and tion, with the opening of new mines: a these later formed the basis of modern min- gold mine in South Greenland in 2005 and eralogical research of Greenland minerals. an olivine mine in West Greenland in 2005. At a site by Aluk near Kap Farvel, Giesecke From being a classical collection of collected a black mineral, believing it to be museum curiosities, the mineral wealth of the well known mineral, hornblende. Greenland has turned into a foundation for Giesecke’s samples from this trip were modern mineral exploitation. Today tradi- stolen by English warships and ended with tion and mineral know-how give us a Robert Allan, a Scottish mineralogist. A detailed picture of Greenland’s mineral Scottish chemist, Thomas Thomson, later resources. It all began in the early 1800s studied the samples and discovered that when the German actor, playwright and they contained a hitherto unknown mineral mineralogist, Karl Ludwig Giesecke, became which he named ‘allanite’ in 1811. All this one of the first to work systematically with was due to the divisions in Europe caused Greenland's mineralogy. Giesecke stayed in by the Napoleonic wars, which also meant Berlin from February to June 1801, and that Giesecke was unable to leave Green- here he wrote a comprehensive ‘manu- land. Since then, allanite has become script’ (350 pages) on the classification of known as a common accessory mineral in minerals. This ‘manuscript’ was preserved the granite bedrock areas the world over. probably because Giesecke kept it with him Following Giesecke’s journey, a research during all the six summers and seven win- tradition of the study of minerals developed ters he later spent in Greenland. Many of rapidly in Denmark and Greenland and this his belongings and mineral collections, influenced the studies of the geology of which Giesecke sent to Denmark on several Greenland and sharpened the awareness of occasions during his travels in Greenland the significance of minerals in geological 1806-13, was seized by British warships during the uncertain years following the Well developed crystal of allanite from the type locality near Aluk in south-east Greenland. Napoleonic wars. Crystal size: 1.2 x 3.5 cm. Photo RB. 2 GO_12.qxp:GO-02 copy.qxp 12/02/08 10:59 Side 3 Geological map of Greenland with mineral localities ▲ ▲ ▲ ▲ ▲ ▲ ▲ ▲ ■ ■ ■ ▲ ■ ■ ▲ ■ ▲ ■ ▲ ▲ ▲ ▲ ▲ ▲ ■ ■ ■ ■ ■ ■ ■ ■ ▲ ▲ ▲ ▲ ▲ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ GREENLAND ■ ■ ■ ■ ■ ■ ■ ■ ■ Mestersvig ■ ■ ■ ■ INLAND ICE ■ ■ ■ ■ ▲ ▲ ■ ▲ ▲ ▲ ▲ Maarmorilik ■ ■ ■ ■ ■ ■ ■ ▲ ■ ▲ ▲ ▲ ■ ▲ ▲ ■ Disko Gardiner Skaergaard ▲ ▲ ▲ ▲ ▲ ▲ ▲ ▲ ▲ Sarfartoq Kangerlussuaq 500 km ▲ ▲ ▲ ▲ Maniitsoq Palaeogene basalts Cretaceous–Palaeogene sediments, Nuussuaq Basin in West Greenland and Kangerlussuaq Basin in East Greenland Carboniferous–Palaeogene sediments, Wandel Sea Basin in eastern North Greenland Ameralik Carboniferous–Cretaceous sediments, North-East Greenland Carboniferous–Cretaceous sediments, Qeqertarsuatsiaat Jameson Land Basin in East Greenland Devonian Basin of North-East Greenland Narsaarsuk Shelf Lower Palaeozoic sediments, North Greenland, Ivittuut Franklinian Basin Trough Meso- to Neoproterozoic sediments and volcanic rocks Ilímaussaq Aluk Caledonian orogenic belt Kap Farvel Palaeoproterozoic orogenic belts Nalunaq Archaean craton Intrusive complexes: Palaeogene in East Greenland, Mesoproterozoic in South Greenland (Gardar Province) ▲ ▲ ▲ ▲ Fault, thrust 3 GO_12.qxp:GO-02 copy.qxp 12/02/08 10:59 Side 4 MINERALS IN GREENLAND processes. Almost 80 recognised minerals contain gold, the platinum group elements, from Greenland were found and described molybdenum, nickel, the specialty metals for the first time. A larger number of tantalum and niobium (in the mineral pyro- known minerals were described in more chlore) as well as several forms of industrial detail, contributing to the completion of the minerals. Industrial minerals are a large geological history. Today more than 500 group of mineral resources which can be minerals from Greenland have been regis- used directly after mining without particular tered; a significant proportion of the world’s refining. This may include minerals for the approximately 4000 known minerals. construction sector, for casting and grinding As the type locality for 77 minerals as well as minerals used as fillers for the (2008), Greenland has been rendered a spe- paper and dyeing industry. Efforts up to cial place in mineral research, even though now may also lead to new finds of dia- many minerals are limited to unusual and monds as well as exploitation of well rare formations. At all events, several of known deposits of rubies. them have shown the way to understand- Mineral exploitation in Greenland can be ing the geological processes and identifying accomplished under very varying conditions, possible deposits of mineral resources. In and this is illustrated in the history of the naming minerals from type localities, miner- Group crystals of red corundum (ruby) in mica three most important mining companies. alogists in complete accord with tradition, schist, Maniitsoq area, West Greenland. From 1856–1987 the mineral cryolite was Longest crystal: 15 cm. Photo OJ. have helped retain the knowledge of the exploited as an industrial mineral near history, geography and geological explo- Ivittuut in South Greenland where a total of ration. Mineral names such as eskimoite, 3.7 million t of cryolite ore was mined from leifite and vikingite have a clear reference to an open pit. The brief period from 1956 to Greenland’s cultural history. Important sites 1963 saw lead-zinc exploitation in Mesters- in Greenland have similarly become world vig in East Greenland, when 0.6 million t of famous through names such as kaersutite, galenite and sphalerite ore were extracted narsarsukite, naujakasite, tugtupite and via underground mining. From 1973 to tuperssuatsiaite. Examination of names 1990 there was extensive zinc-lead-silver which directly refer to important people in mining in Maarmorilik, from where 11.3 early geological exploration such as bøg- million t of ore containing sphalerite and sil- gildite, bøgvadite, kornerupine, lorenzenite, ver-containing galenite were extracted in rinkite, steenstrupine and ussingite, brings underground mining. All these activities to mind the Danish exploration work. A ceased because the reserves of ore had similar list of minerals named after contem- more or less been exhausted. porary geologists is just as extensive and a reminder that exploration is still alive and well. Blue Lazurite cystals surrounded by white scapo- Cryolite – Greenland’s ’white lite and black amphibole, Maniitsoq area, West gold’ Greenland. Size of sample: 5.0 x 5.5 cm. Photo ’White gold’ has with good reason become OJ. Minerals and mineral resources the term associated with exploitation of cry- Mineral resources have a high priority in the primary in-situ deposits. This contrasts with olite in Greenland. This wealth meant that socio-economic development of today’s the secondary supergene deposits where the owners of the mining company really Greenland. Such priorities require the pres- the mineral resources are enriched in gravel did have free access to something which ence of a large number of mineral resources and sand in rivers and on beaches, formed approached a ‘vein of gold', or better, for which form the foundations of mineral by erosion of the mountains. Many of the money flooded in and expenses were small. exploitation and mining, just as in other secondary deposits in Greenland were prob- There was no way of foreseeing this adven- parts of the world. From 1990 to 2004 ably removed by glaciers of the Ice Age. ture when mining began at the site in there was no exploitation of minerals, after The geological conditions in the Greenland 1856. almost 150 years of mining. On the other geological environment are now well The cryolite deposit was first described in hand, there has been great activity in the known and the many useful minerals pro- detail during the exploration in 1806- exploration for new deposits and surveys of vide good opportunity for identifying locali- 1813 carried out by the mineralogist K.L. existing finds. Mineral resources known in ties where exploitation of mineral resources Giesecke. The chemist, Professor Julius Greenland so far are primarily located as the could take place. Known mineral deposits Thomsen, described a process whereby cry- 4 GO_12.qxp:GO-02 copy.qxp 12/02/08 10:59 Side 5 MINERALS IN GREENLAND Piles (box formed) of cryolite on the quay ready for loading in Ivittuut 1920, South Greenland. Photo: IMMM archive. Insert : Cryolite rock (white) with siderite crystals (brown) from the Ivittuut cryolite mine, South Greenland. Size of sample: 8 x 10 cm. olite could be converted into soda, which at metal had already been demonstrated in Since the issue of the first exploitation con- that time was an important element in a 1825 by the Dane, Professor H.C. Ørsted, cession in 1859, the state had secured itself spiralling chemical industry.