Swedish minerals and mineral shows 1995.
I went to Stockholm to photograph minerals, and was met at the airport by Curator of Minerals, Jorgen Langhof, who drove me straight to the Naturhistoriska Riksmuseet (the Swedish Museum of Natural History) in his beloved Volvo "Amazon." He provided a crash course, so to speak, in other classic Swedish cars en route. We lived and breathed minerals and mining for a good 12 to 18 hours a day for the rest of the week. On our one brief break we took a tourist trip into the city to visit the Vasa, a sixteenth century state-of-the-art warship that sank on its maiden voyage (like England's equivalent the Mary Rose, the art wasn't quite up to it). The good ship Vasa, raised from the sea bed after 400 years, is housed in a custom-built museum that is quite stunning. With its remarkable range of interpretation of the ship, the sea, of maritime lore, superstition and battle, this is one of the finest museums I have ever visited. The memory of the sea-blackened ship looming up from its dry dock will stay with me forever.
Back at the SMNH I was allocated a small basement room packed with bizarre minerals from Langban, one of the world's most remarkable mineral deposits. Quirks of geochemical history had deposited an unusual assemblage of elements at Langban - iron, manganese, arsenic, antimony, beryllium, lead, etc. - and mixed and matched them with complete disregard for "normal" mineralogy. For a few decades around the turn of the century Langban produced unknown after unknown, many of them noted by keen-eyed Swedish dealers and collectors like Gustav Flink and Karl Finneman, the latter an ore-picker at the mine. But despite the remarkable mineralogy, Langban specimens are relatively unknown in the international collector community. This may owe as much to history as rarity since Langban bloomed during one of the dark ages of mineral collecting. Be that as it may, the SMNH has a huge store of these remarkable specimens, the largest single-site collection in the world and an incredible research resource. The SMNH mineralogy department is producing an English-language book on the minerals of Langban, which will be the first complete treatise on these fascinating minerals in any language. I worked my way through scores of exotic specimens which up till then were only names in mineralogy texts to me: perite, allactite, akrochordite, paulmooreite, molybdophyllite, and eveite (the manganese analog of adamite, whose naming once elicited much criticism for its flippancy). Locked in some of these intriguing, and often surprisingly attractive, minerals is some fascinating chemistry: sweden-borgite is sodium beryllium antimonate, bromellite is straight beryllium oxide, Langbanite itself is an appropriate manganese antimony silicate, and there are lead silicates and almost every combination of lead, chlorine and arsenic that you can think of. I'm sure that many readers of their new book will be agreeably surprised to find that not only are these minerals chemically interesting, they are often very beautiful as well: raspberry-red sarkinite globules, deep purple allactite, bright yellow trigonite in simple triangular plates, and some of the prettiest nadorite crystals you ever saw, adamantine yellow on their black matrix.
Among other treasures in the museum is the remarkable collection of Hjalmar Sjogren (1856-1922). Sjogren was a dedicated and meticulous collector. His taste was wide-ranging but refined, and his attention to detail awe-inspiring. In its own way the Sjogren collection is as stunning as the specimens and documentation of the collection of Frederick Ashcroft in the British Museum (Natural History) in London. Sjogren built his collection in the closing years of the nineteenth century, housing it in custom-made beechwood cabinets each elaborately inlaid with his initials and the date of manufacture. On top of each is a showcase glazed with beveled plate glass and fitted with stepped shelves, each bearing rows of fine specimens on custom-made polished wood pedestals. His labels are written out in a wonderfully neat calligraphic hand, and the drawers in the lower parts of the two-door cabinets are filled with black-velvet-lined trays. When Sjogren became curator of minerals in 1901 he donated his collection to the museum. The donation documents themselves are works of calligraphic art, with illuminated capital letters and elaborate script. He continued to work on the collection for the rest of his life. Every major museum should have a collection like this, to amaze and inspire collectors in the realization that collecting is not just about accumulating specimens, it's about storage, preservation and documentation, too.
Tom Moore visited the Riksmuseet in 1990 and wrote up his trip in the Mineralogical Record (vol. 22, p. 45-46). He was disappointed with the mineral displays and would be even more so today, now that the main mineral gallery has been closed and only a small temporary exhibit of minerals is open to the public. Nevertheless, this display contains some marvelous pieces, and the informed visitor will be suitably impressed by such Swedish specialties as the world's best pyrosmalite, edingtonite and cobaltite. The ten cabinets of the Sjogren collection are also on display, replete with fine Russian pegmatite minerals, Langban and Franklin oddities. British calcite and barite, and old American wulfenites in their cabinet-top showcases.
Stockholm Show 1995
The day after I arrived in Sweden the Stockholm Mineral Show opened. This weekend-long show is in its infancy (this was its second year), and is mostly devoted to lapidary and schmuckstein. There were a few serious dealers in minerals, although some expected foreign dealers did not come, perhaps as a result of a badly timed strike by the Swedish national airline, SAS. The show had two small special displays, one from local collectors and another from the Riksmuseet. The latter was devoted to pegmatite minerals and contained a few of their specialties described in Burchard and Bode's Mineral Museums of Europe, notably a large and fine elbaite from Elba sprouting bi-colored prisms from a large granitic matrix, and a few lovely single crystals on delicate wood-mounted brass clips from the collection of Axel Hamberg (including a superb deep blue euclase).
The main body of the show was disappointing for the serious collector, but the entrance hallway contained a few Swedish and Russian collector-dealers with some particularly interesting specimens. I am indebted to Jorgen and to mineralogist and collector Erik Johanssen for the following invaluable notes on these occurrences. Among the more interesting and spectacular recent finds in Sweden are babingtonite crystals of international importance. The first specimens found several years ago were sold and traded as augite crystals, but suspicions about the true nature of the material led to analysis at the SMNH, which showed it to be babingtonite. The crystals are sharp, jet-black and prismatic, often very lustrous, and occur in a nice contrasting combination with small quartz crystals and, rarely, grass-green epidote crystals. The locality, a couple of small old limestone quarries named Gronsjoberg, is situated between Borlange and Falun, the famous old copper mine in south-central Sweden. The limestones in the neighborhood are contaminated with many different skarn minerals such as garnet, epidote, wollastonite and vesuvianite which were formed by regional or contact metamorphism or both. The babingtonite-bearing zones were probably formed by late hydrothermal activity. The first babingtonite finds at Gronsjoberg were restricted to occasional dump material found by local collectors searching for garnet crystals. But in September 1993 a big in situ find was made in an outcrop, between two of the small quarries, consisting of large quantities of naturally leached-out pockets. Deeper down were pockets filled with calcite, which after its removal were shown to contain some of the best and most lustrous babingtonite crystals. They are often packed tightly together making very rich specimens, but much of the material from the roofs of the elongated pockets shows superb single crystals scattered on small colorless quartz crystals to form the most aesthetic and valuable specimens.
Another interesting find, which actually was a rediscovery of an earlier known small locality, was made a couple of years ago but is still on everybody's lips. Garnets, probably with a large grossular component, were found in a small old prospect near the little mining village Herrang, north of Stockholm. The occurrence is a garnet skarn rock with associated scapolite minerals among others. In narrow calcite-filled pockets and fractures red to reddish brown garnet crystals in sharp and occasionally very perfect single dodecahedrons occur in sizes up to 3 cm. The calcite is easily removed, and many lustrous specimens have reached Swedish collectors.
The Chibougamou (Quebec) cubanites are known worldwide and are of unbeatable sizes; a very few such specimens have made it to Sweden, but now the Swedes have some consolation. Early this spring what seems to be the first free-grown cubanite crystals in Scandinavia (perhaps in Europe?) were found in a newly blasted railway-cut at Kalkugnstorp, some 70 km west of Stockholm. The small cut was accessible for a few months, and consisted of an ordinary gneiss with a narrow zone of a pyrrhotite-pyrite mineralization, which, probably through percolating surface water, has been partly decomposed. The result is a greenish clay-rich rock with open cavities in between large subhedral pyrite crystals. In these cavities cubanite occurs sparsely as long prismatic or complex flat multiple twins. The prisms reach 1 cm. Rarely the crystals show a beautiful bluish purple tarnish. Associated minerals include crystals of pyrrhotite, pyrite, galena and adularian orthoclase.
During the last five years a range of new and interesting pegmatite minerals has been encountered in Sweden. In the mine dumps of the famous Uto area (a pretty island in the Skerries archipelago of Stockholm) lithium pegmatites have been an interesting objective for keen-eyed collectors and mineralogists. The first notable find was pollute, actually the second Swedish locality. Though Uto is the type locality for the LCT-type pegmatites (Lithium-Caesium-Tantalum) - and being also the locality for the original find of the element lithium and the minerals petalite, manganotantalite and holmquisite is well picked-over - many other minerals have recently been found there. Among the more exciting finds are boron-bearing chiavennite in sprays up to 1 cm (the third world occurrence), zoned genthelvite-helvite crystals, stokesite and wickmanite. Nice micromounts of milarite, bavenite and manganite have also turned up. These associations have been investigated at the SMNH and an article is under preparation.
Another milarite locality was discovered in 1993 at Hogsbo in the southern part of Gothenburg in western Sweden. In an abandoned pegmatite quarry drusy quartz-bearing material was found to contain gray-white to greenish yellow milarite crystals up to 5 mm. Further collecting has resulted in larger crystals, actually in competition with the famous Jaguaracu milarites of Brazil. One crystal 1.6-cm long and 1 cm wide, now in the SMNH collection, was found in a big boulder. Even larger crystals (up to 2.5 cm), though bent and crude, have been found by private collectors - the second largest pegmatite milarites in the world? The paragenesis includes bavenite and fluorite, the typical accessory minerals in milarite-bearing environments.
Further north in the middle of Sweden a pegmatite quarry at Sels Vitberget near Kramfors was worked in the 1960's for beryl and quartz. It has recently been shown to contain many hydrothermally decomposed beryl crystals. The first find was noted in 188, but during the last five years in situ finds have been made, including beryl crystal sections up to 20 cm in diameter completely replaced by bertrandite and euclase, together with quartz. Parts of the former beryl are very drusy and contain euclase in colorless semi-transparent crystals up to 1.5 cm long and red-stained bertrandite crystals up to 5 mm; small phenakite crystals have also been noted.
During the 1980's, bright yellow to pale yellow-brown and rarely greenish gray, transparent to opaque barite crystals were found in the Silurian limestone of Gotland Island in the middle of the southern Baltic Sea. Recently, very attractive specimens were collected, in which bright yellow tabular barite crystals together with colorless calcite crystals occur in a fossil-bearing limestone horizon. The crystals may reach several cm in size. Among the older finds an impressive 4-cm yellow barite floater, from a clay-filled pocket, must be mentioned. It is probably the best Swedish barite ever found.
Turning to the more exotic mineral names we must start with the Langban oddities. Much could be said about this remarkable spot on the earth's crust, but one thing is for sure, many of the minerals are unique and very difficult for the average collector to recognize. Though much of the nice specimen material disappeared into collections around the world, especially the SMNH, in the early 20th century, interesting finds and new associations are still uncovered every year. Much of this work of discovery is contributed by the members of the Langban Society, founded in 1984, but other collecting visitors may reap Langban specialities after observant and patient collecting. During recent years rare things like welinite, bromelite, trimerite, pyrobelonite, wickmanite and tetrawickmanite have been found in dump material, though most of them had to be identified by means of x-ray diffraction analysis. Rare minerals have also been yielded by some of the smaller, neighboring Langban-type deposits, perhaps the most interesting being Jakobsberg, an old iron-manganese mine south of Nordmark, the site for the newly described mineral lindqvistite, a lead-manganese-magnesium-iron oxide resembling plumboferrite from which it is hard to distinguish. Other newly-made dump finds include hancockite - the second world occurrence - sahlinite, katoptrite and ericssonite.
The other small-scale manganese-iron occurrence in the Filipstad area is the Harstigen mine, famous for its classic rhodonite crystals and as the type locality of the rare beryllium minerals trimerite and harstigite, and the manganese arsenates brandtite and flinkite. The first natural lead crystals were found and described from this small mine too. Much of the dump material has been searched thoroughly, but specimens of interest still show up. During the last two years good trimerite and two beryllium minerals new for the locality, bromellite and helvite, have been found, the former as a 3.5-mm crystal aggregate in a calcite-filled skarn fissure, and the latter as crude flat crystals several centimeters across in narrow fissures in an iron ore skarn association.
At Nordmark, an iron ore field consisting of several mines with some small manganese orebodies has yielded specimens as well; dump and in situ finds of several interesting minerals have been made, including rare manganese arsenates such as synadelphite, hematolite and allactite in small but attractive micromounts; also filipstadtite, manganostibite, katoptrite and alabandite. In different limestone-dolomite associations the boron-rich minerals harkerite, ludwigite and fluoborite have been identified, though not together. The harkerite forms crystals to 5 mm with vesuvianite and other species. Among the classic skarn-fissure minerals pyrosmalite and hedenbergite have been found, the latter as druses of lustrous green-black crystals to 1 cm in one of the mine walls.
The phosphate minerals of the pegmatites at Norro, a peninsula of Rano Island just south of Uto Island, are Swedish classics. Triphylite and other phosphates were described from here in the early 1940's. More recent notable finds include the beryllium phosphates herderite, vayrynenite, beryllonite and hurlbutite, all as late-stage products more or less replacing beryl. Some 20 km to the west (we're now on the mainland south of Stockholm), is a large abandoned limestone quarry with interesting pegmatite minerals. The quarry is named Stora Vika, and has been the home collecting area for Stockholm-based collectors for the last 25 years. In recent times interest has been more and more focused on the pegmatites transecting the limestone quarry. Notable finds include helvite (zincian), bityite, an unknown Ca-REE-Be-silicate and milarite (yttrian). At the moment the collecting activity has declined, but there is still potential for interesting finds.
In the two active mines of Garpenberg new and sensational finds have been made during the last two years. Specially notable are microcrystals of samsonite, pyrostilpnite and pyrargyrite, large masses of alabandite, crude pinkish gray crystals of wenkite up to 1 cm and apophyllite in colorless to white crystals up to 2 cm, rarely associated with white harmotome crystals of the same size.
In a small old dump in the orefield of southern Haborshyttefaltet, just south of the famous pyrosmalite locality at Nordmark, poor crystals up to 5 mm of greenish brown ferropyrosmalite have been found. They occur in thin fissures unfortunately often coated with a thin sulfide layer. The Leveaniemi deposit in northern Sweden, renowned for violet strengite, has produced some other rare phosphates during the last few years. Among them paravauxite, montgomeryite-kingsmountite and tinticite should be mentioned.
Going a couple of hundred of kilometers to the south into the Skellefte ore field, where the famous and now-closed Boliden mine is situated, we find the largest active gold mine in Europe, the Bjorkdal mine. This huge open cut yields some 2,000 kilograms of gold every year. The gold-bearing quartz veins also host the rare bismuth telluride tsumoite as gray masses and brittle plates. Another interesting gold mine is the Akerberg mine, some 30 km north of the Bjorkdal mine, where a lithium-bearing pegmatite was encountered during preparatory blasting. One or more pods or local units in a schorl-bearing pegmatite proved to contain, among other things, lumps of pollucite, also elbaite, petalite and amblygonite, and as rare accessory minerals a few lumps of allemontite with native arsenic.
From the type locality of the copper selenide berzelianite, Skrikerum in southeastern Sweden, several selenium-bearing minerals have been newly identified: athabascaite, bukovite, umangite and chalcomenite are the additional phases. The last pegmatite mineral discovery I'll mention originates from middle Sweden, where prospecting for tin in pegmatites has revealed the rare tin sulfide herzenbergite as gray metallic replacement rims in and around cassiterite. The locality is known as Jarkvissle and is situated some 55 km northwest of Sundsvall. And, finally, in a newly abandoned quartzite quarry at Stakholmen, about 50 km southwest of Sundsvall, huge, elongated, divergent masses of gray kornerupine have been discovered. Aggregates up to 30 cm long are said to have been found.
Kopparberg Show 1995
The weekend I left Sweden coincided with the best Swedish mineral show, that in Kopparberg. Tom Moore wrote a good account of this northern answer to Ste-Marie-aux-Mines in the Mineralogical Record a few years ago (vol. 22, p. 46-48). I would've loved to have gone this year, but I was due in Ste-Marie itself in a week and in between I needed to do some work. Reluctantly, therefore, I said my farewells and left Jorgen and Erik to take the trip without me. I am indebted to them for this report on the show:
Extremely bad weather (i.e. heavy rain and wind) threatened to thwart Kopparberg this year, which by tradition is an outdoor event. In the end, though, the show went on, albeit with some reduction in the numbers of visitors, but the main effect was just unusually damp mineral collectors. As in recent years, the presence of eastern European dealers and collectors was quite strong and the highlight of this year was perhaps a suite of minerals from the already classic Yubileynaya ("Jubilee") pegmatite of the Kola Peninsula, including good crystals of rarite, mountainite, laplandite and leucosphenite. Other interesting minerals from Kola included sazhinite-(Ce), nordite, leucophanite and meliphanite. The occurrence of herderite at Chukotka, Russia, was represented by a few specimens of pale wine-yellow crystals in small, loose groups. Also among the minerals from alkaline rocks, Richard Scholer of Denmark again had an array of material from the Illimaussaq intrusion of southern Greenland. Particularly interesting were tundrite-(Ce) in bronze-colored to yellow, hair-like crystals in open cavities, rich pieces of cuprostibite, and unusually large specimens of the beryllium silicate chkalovite in pods up to 5-7 cm.
Commanding serious attention was a lot of very good material from the Poona area, brought by an Indian dealer. This of course included much of the new cavansite, but definitely more interesting were the different types of heulandite: as reddish or salmon-colored aggregates associated with white zeolites and apophyllite, and as almost opaque, green (through numerous inclusions of chlorite), complex floater aggregates to more than 5 cm. The prices were initially a bit on the steep side, but as the increasing rain soaked through the poor dealer's business suit (totally un-Kopparberg attire), his prices sank rapidly.
A definite one-of-a-kind was a magnificent zircon specimen from the well-known occurrence at Seiland in northern Norway. Contrary to what has been previously available for these dark reddish brown giants, these zircons were not intergrown but occurred in an open cavity, later filled with a fine-grained barite-like substance. Meticulous preparation work had stripped the latter away and exposed several tens of well-formed, 2 to 3-cm crystals grouped together in the cavity. This must without question be among the finest matrix zircons ever to have come out of this locality. According to some sources, zircon mining activity has been low on Seiland in the last years. Should more material of this type be around there, we must hope for a reactivation!
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|Title Annotation:||What's New in Minerals|
|Publication:||The Mineralogical Record|
|Date:||May 1, 1996|
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|Next Article:||Ste-Marie-aux-Mines show 1995.|