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The Evje - Iveland area in southern Norway is a forested mountainside with sparse population, which hosts hundreds of small to medium sized pegmatites with a remarkable variety of different minerals. The pegmatites were mined primarily for feldspar for use in the ceramics industry, but this activity ceased down in recent decades. Giant crystals of feldspar, quartz and mica up to several metres large were not uncommon, though their remains are difficult to be documented these days, as most of the old quarries are overgrown and filled with water.
What makes this pegmatite field so special is the diversity of its minerals, with most of them occuring in sizeable, if not giant crystals. Orthite crystals a m long ? Blocky blomstrandine 40 cm across ? Thortveitite of 10 cm length ? Its all there and much more. And even very rare minerals tend to occur in super sizes... More than 100 different mineral species have been described to date and only few of them are small. Here are some more outstanding examples : Beryl crystals up to 3 m, Euxenite : 20 cm, Fersmite : 6 cm, Monazite : 18 cm, Strüverite 6 cm. Getting bored ? Ok, we stop here for once, but there are even more - in fact the Evje - Iveland pegmatitic area is a prime candidate for supplying many entries into our list in the future.
As stated above, today most of the pegmatite quarries lie dormant and overgrown in dense birch tree - blue berry thickets. However, the whole area is still famous for its mineral wealth and many a mineral collector and tourist come here to go mineral hunting. Some of the quarries - namely the Landsverk I pegmatite at Evje - has been officially turned into mineral hunting grounds and several mineral museums in the area - Evje Fennefoss, Setesdal Mineral Park and the Iveland Kommune museum - are open to the public. The community of Evje itself has created the "Evje mineral sti" where tourists can wander along the old paths leading to the pegmatites and the nearby abandoned Flat nickel mine, which used to be the largest nickel mine in Scandinavia.
So, giant crystals and rare minerals still play an important role in this otherwise tranquil part of the world and we wish our best, that this public interest in minerals of the Evje - Iveland area will keep growing !
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The Evje - Iveland pegmatites in a nutshell :
Mineralogy : |
Large - giant crystals of several silicates - beryl, blomstrandine,
orthite - occur in extremely coarse grained mica - quarz - feldspar matrix |
Crystal Size : |
The rarer silicates may reach about 20 cm size or slightly above, the more common
ones like mica , feldspar and quartz reach up to several meter. |
Geology & Origin : |
Pegmatitic - pneumatolytic, whereas there are two types of pegmatites :
granitic microcline - quartz veins and larger, late hydrothermal cleavelandite - quartz pegmatites |
Current status : |
Very active mining in the last decades, now mostly dormant. Limited mining takes place
for specimen excavation in form of the Evje Mineral Park. Important pegmatites and
outcrops are protected and often signposted. |
Remarks : |
The Evje and Iveland Communities welcomes visitors with geological / mineralogical interest. |
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Other notable & famous feldspar occurences :
Note : Strictly speaking, the term "Feldspar" refers to a large group of tectosilicates such as Albite, Anorthite, Orthoclase and some others. For more information about the more common members of the feldspar group please
click here.
Members of the feldspar group may be (apart from quartz possibly) the minerals with the largest crystals in existence. There are several rumours around about sizeable quarries in a single feldspar crystal. An example is the Devils Hole mine, Colorado, where a crystal of the size 50 x 36 x 13 m is reported from. However it is difficult to verify those rumours, even on site, as it is not easy to determine accurately the true extent of a single crystal that large.
Feldspar crystals of one meter and more are a common constituent of pegmatites worldwide and too many to name here. In fact, pegmatites are defined by the gigantism of its minerals, of which members of the feldspar group are among the most common ones. These feldspar crystals usually Do NOT exhibit any freely developed crystal planes, but rather form giant crystalline "feldspar - grains" swimming inmidth of other feldspar (quartz, mica etc.) grains. There are however many noteworthy occurences of freely developed feldspar crystals, which may reach considerable sizes :
- Excellent tabular cleavelandite ( = variety of albite ) clusters up to 15 x 10 cm occur in large cavities in the Rutherford Mine, Virginia and in the Pikes Peak massive, Colorado. Other spectacular cleavelandite crystal "books" are known from the tourmaline pegmatites of Pala and Hercules mine, California.
- Pericline, another variety of albite, is known as a major constituent of hydrothermal alpine fissure mineralization. Many alpine localities with excellent specimen are known, whereas the largest reported pericline crystals, reaching almost 20 cm - came from Gibelmatte in the Binntal, Switzerland.
- Exceptional well crystallized orthoclase crystals are known from many granite pegmatites such as Strzegom / Striegau in Poland and from Baveno in Italy. Another renowned locality are the alkaline pegmatites of Mt. Malosa, Zombas, Malawi, where excellent orthoclase crystals may reach 20 cm and more and often form perfect "Karlsbader" twins.
- Gemmy yellow Orthoclase crystals of up to 10 cm are known from a small locality at Itrongay, Madagascar
- Splendid green amazonite crystals, a variety of the microcline feldspar, up to 40 cm and more are known to occur at various localites such as Pikes Peak, Colorado and recently from Konso, Sidamo Province, Ethiopia.
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Beryl crystals, 1,4 m long from Landsverk 1, Evje,
on display in Iveland Mineral Museum
Source : www.smartminerals.com
Large Blomstrandine (= Aeschynite - Y) crystal aggregate with single xls up to 40 cm on display in the
Setesdal Mineral Park
Source : www.smartminerals.com
Part of a large muscovite crystal, Landsverk 1 Pegmatite, Evje
Photo : Giant Crystal Project
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| Resources and relevant weblinks :
Several museums in the area exhibits mineral specimen and geological / mineralogical information about the area. There are at least two good websites devoted to the mineral treasures of the Evje - Iveland area : a field trip report with many mineral photos 2002 by www.smartminerals.com and the Virtual Museum of Norwegian Minerals by Michael Krause.
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