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The Evje-Iveland area has become famous among scientists and mineral collectors thanks to the hundreds of pegmatite mines and quarries, yielding more than 100 different minerals. It's also the best developed area in Norway, offering several museums, shops and other geological attractions for a broad public. This article intends to be an introduction to and overview over the Evje-Iveland district, without pretending to be comprehensive. In addition to a geological overview, I will also present some of the more interesting minerals. Finally, you will find links to the websites of the individual attractions, in as far as these are available. HISTORY For the timebeing I have little information about the exact history of the exploitation of the pegmatites in the Evje-Iveland district. Mining began around 1880, and the famous Landsverk mine was among the first to be taken in exploitation. In this period quartz was mined in connection for use in the smelter of the nickelmines. In 1896 the Setesdal railroad was taken into use, and it became profitable to mine the potassiumfeldspar (microcline). The feldspar was transported by train to Kristiansand, and was from there exported to Germany and England for the production of porcelain. Alone in the Landsverk mine 20.000 tons of feldspar were taken out in the period till 1928. I have no production figures of the other mines for the timebeing. Nor am I sure exactly when the last mine/quarry was abandoned, but to day none of the pegmatites is being exploitated. GEOLOGY The Evje-Iveland district consists mainly of Precambrian amphibolites (1200 M.y.), in which younger (900 M.Y.) granitic magmas and solutions have intruded, forming granites and granitic pegmatites. Especially in the northern part of the area is it possible to observe the pegmatites as ridges in the landscape. The pegmatite veins often follow the layering of the amphibolite, but just as often they cut through the amphibolite. The pegmatites are being divided in at least two different types. The first being microcline-quartz veins of magmatic origin, the second being younger cleavelandite-quartz veins of hydrothermal origin. A possible third stage consists of dark-red microcline and granular albite. The pegmatites are usually small, lense-shaped or irregular. The largest pegmatites can be found at the borderzone of the amphibolite in the southern and northern parts of Iveland, and in Evje. These pegmatites are often very coarse grained and can contain huge individual crystals of both the common constituents of the pegmatites, but also of the rarer minerals. Cryptic granite is common at the contact of the pegmatite with the amphibolite, while in the central zones feldspar crystals of several meters are no exception! The magmatic pegmatites are the most common and usually far larger than the hydrothermal pegmatites. The magmatic pegmatites consist of red or gray perthitic microcline, graywhite/yellowish plagioclase, quartz, biotite and muscovite. Accessory minerals can be beryl, garnet and many others. MINERALS The list over the minerals from the Evje-Iveland district is long, far too long to describe all the minerals individually. Instead I will concentrate on the more basic species and some of the interesting, typical pegmatite minerals. Especially interesting are the minerals containing Rare Earth Elements, beryllium, scandium, uranium or thorium. Also here I had to focus on a number of the more common/interesting species. It is my intention to update the descriptions later this year, having planned to spend at least some weeks in this area. AESCHYNITE-(Y) : previously known as blomstrandine or priorite, has been found in Vestre Frikstad and Kåbuland, both in Iveland. ALLANITE : is one of the more typical pegmatite minerals. The crystals are usually poorly developed and metamict, due to a certain content of uranium/thorium. Crystals up to hundred kilo have been reported. BERYL is definitely one of the most imposing minerals from the area. Although much more common as crystals up to a few centimeters, crystals weighing up to 3 ton are described from Iveland. This crystal had a lenght of 3,25 meter and diameter of 1,1 meter. The color of most of the beryl is pale yellowish, but nice blue colored aquamarine is also reported from several of the quarries. To a certain extent the aquamarine has been used for cutting gemstones. As an alteration product of beryl, the minerals bavenite and bertrandite have been found. COLUMBITE EUXENITE FELDSPAR MINERALS : are among the main constituents of the pegmatites and were mined for use in the ceramic industry. Important was in the first place microcline as the most common feldspar mineral. Albite is commonly found as cleavelandite with a pale bluish color. Good albite crystals are reported from the Landsverk 1 quarry in a brecciated zone. FERGUSONITE FLUORITE has been found in many of the pegmatites. Beautiful octahedral purple, crystals freegrown in cavities were found in the Landsverk quarry in Iveland. GADOLINITE MAGNETITE is a very common black, metallic mineral in the pegmatites. Sometimes collectors confuse magnetite with the much more interesting REE-minerals or with uraninite. MICA MINERALS are very common in granite pegmatites in general and also in the Evje-Iveland district. Most common are muscovite and biotite. Also lepidolite has been found, not as the lila colored mineral we are accustomed to, but as a pale yellow-green mineral. MONAZITE POLYCRASE QUARTZ is one of the main constituents of the pegmatites, and is found in large masses that once were mined for use in the nickel smelters of the Flåt mine. SPESSARTIN THORTVEITITE is among the most interesting minerals from the Evje-Iveland pegmatites. In 1910 a local person by the name Olav Thortveit sent in an unknown mineral to the museum in Oslo. In 1911 the norwegian geologist Schetelig described this mineral as the first scandium mineral found in the world. The name thortveite was given in honor of Olav Thortveit. Later it was found out that already in 1903 another collector had found samples of Thortveitite. Not knowing the true identity of this mineral, he named it epidote with a questionmark. Thortveite is usually found as long-prismatic crystals, greenish, gray or pale gray-green of color. The largest described crystal weighed 200 grams. There has been small-scale mining for thortveite, and some 50 kilos were mined over a period til 1961. Thereafter the production has been marginal. Thortveitite has been found in a number of occurrences, among which Ljoslandknipen, Landsverk, Eptevann 2, Håverstad, Tuftane etc. The remaining minerals are listing according the group to which they belong. I don't believe this list is complete, nor can I be sure that there not might be one or two minerals that in later times turned out to be wrongly identified and consequently should have been stroked from the list. ELEMENTS : bismuth SULPHIDES : bismuthinite, chalcocite, chalcopyrite, molybdenite, pyrite, pyrrhotite. HALOGENIDES : fluocerite OXIDES : cerianite, chlorite, fourmarierite, hornblende, ilmenite, ilmenorutile, laumontite, microlite, rutile, samarskite-(Y), tantalite, thorite, uraninite, yttrotantalite CARBONATES : bastnaesite-(Ce), calcite, malachite, tengerite-(Y) PHOSPHATES : apatite, monazite-(Ce), xenotime-(Y) SILICATES : betafite, cerite-(Ce), davidite, epidote, prehnite, rowlandite(?), stilbite, stilpnomelane, thalenite, titanite (also as "yttrotitanite"), toernebohmite-(Ce), tombarthite, tourmaline, topaz, thorogummite, uranophane, vandendriesscheite, yttrialite, zircon LINKS Setesdal Mineral Park in Evje: underground museum, the first of it's kind in Norway REFERENCES
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