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Global stone heritage: Larvikite,

TOM HELDAL*, G. B. MEYER & R. DAHL Geological Survey of Norway, Box 6315 Sluppen, 7491 Trondheim, Norway *Corresponding author (e-mail: [email protected])

Abstract: Larvikite is a peculiar and unique monzonitic rock originating in the Carboniferous– Permian Oslo , SE Norway. The blue iridescence in the crystals made the rock particu- larly attractive as ornamental stone, and since the start of industrial scaled production in 1884, the use of larvikite has reached every corner of the global community. With resources for hundreds of years, the region will produce larvikite blocks far into the future. The production of larvikite has changed significantly during the last decades, towards more sustainable production finding new applications and markets for excess rock in the quarries. The significance of larvikite in the global market has also created a wider appreciation of the rock in the Norwegian society, acknowl- edging the rich history of larvikite production and use.

The term ‘Larvikite’ is applied for a range of predominantly in its southern part (Fig. 1). The pio- peculiar monzonitic rocks within the southern part neering work by Brøgger (1890) on these igneous of the Carboniferous 2 Permian Oslo Igneous Pro- rocks made a significant contribution to the under- vince (Fig. 1). They have for more than a hundred standing of rift-related magmatism, and he also years been appreciated as one of the world’s most suggested that the larvikites are the plutonic equiva- attractive ornamental stones, and at present, its pro- lents to the once overlying massive sequences of duction and use is more extensive than ever. The rhomb porphyry lava flows (latite) exposed in the main reason for the continuous success of larvikite surrounding areas. Neumann (1978) later provided on the world market is the blue iridescence dis- geochemical evidence for this. played on polished surfaces, which is caused by A new breakthrough in the interpretation of the optical interference in microscopic lamellae within larvikite complex came in the 1970s. Petersen the ternary . This feature was beautifully (1978) suggested that the larvikite complex is com- described by Leopold von Buch, who travelled the posed of several, ring-shaped intrusions, becoming area 1806–1808 (von Buch 1810): younger from east to west (Fig. 2). He suggested the presence of eight such ring fragments (numbered All cliffs and rocks shine like they are from a strange world, such we are not used to see. This freshness I–VIII) based on topographic features, magnetic and lustre in the feldspars, such large crystals, the anomalies and field observations of some of the con- extraordinary blue colour and the frequent labradoritic tact zones (chilled margins) (Fig. 2). Furthermore, play of colours. Petersen (1978) observed a systematic change in the mineralogy from -bearing larvikite in the von Buch discovered that these plutonic rocks con- east towards nepheline-bearing larvikite to the tained abundant zircon, and named them zircon- west, approaching the lardalite and nepheline sye- syenite. The name ‘larvikite’ was first applied by nites in the ‘centre’ of the plutonic complex. This the geologist Waldemar Christopher Brøgger led Petersen (1978) to suggest a sequential evolution (1852–1940), who was the first to describe these from saturated to under-saturated magma fluxes. rocks in detail, aided by the newly invented polariz- This could result from either multiple caldera col- ing microscope (Brøgger 1890). The name has its lapses or a system of multiple ring intrusions from origin in the small coastal town of , situated a deep-seated parental magma chamber (Neumann almost right in the centre of the main plutonic et al. 1977; Neumann 1978, 1980; Petersen 1978; complex of larvikite. Neumann et al. 1988). Neumann (1980) confirmed Petersen’s model of the separate ring intrusions by geochemistry, and of the larvikites also showed geochemical evolution patterns within Magmatism and emplacement each ring intrusion. Dahlgren et al. (1998) con- firmed the progressive evolution of the ring intru- Larvikite and associated plutonic and volcanic sions through time by U–Pb dating, giving a range rocks compose a significant part of the bedrock of ages between 297 + 1.2 Ma (eastern larvikite) within the Carboniferous–Permian Oslo Rift, and 293.2 + 1.3 Ma (western larvikite). Nepheline

From:Pereira, D., Marker, B. R., Kramar, S., Cooper,B.J.&Schouenborg, B. E. (eds) 2015. Global Heritage Stone: Towards International Recognition of Building and Ornamental Stones. Geological Society, London, Special Publications, 407, 21–34. First published online November 27, 2014, http://dx.doi.org/10.1144/SP407.14 # The Geological Society of London 2015. Publishing disclaimer: www.geolsoc.org.uk/pub_ethics Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 1. Map of the Oslo Igneous Province, Norway, and main larvikite production area. syenite, being the youngest intrusion in the se- in the rift formation, i.e. between the early volcan- quence, was dated at 292 + 0.8 Ma. More recently, ism (basalt fissure eruptions and plateau basalts) Larsen & Olaussen (2005) made a model for the and later caldera formation. evolution of the Oslo Rift where the larvikite/ Airborne magnetic and radiometric surveys rhomb porphyry lavas define an intermediate step (Mogaard 1998; Beard 1999) confirmed the pattern Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 2. Structure of the larvikite complex as proposed by Petersen (1978). Figure from Oftedahl & Petersen (1978). of ring-shaped intrusions established by Petersen larvikite types used for dimension stone, the (1978), however, not along exactly the same lines ternary feldspar are composed of flame-like to as he proposed. The magnetic map furthermore dis- patchy intergrowths of various phases of feldspar. plays two large fault structures (Farrisvann Fault, Individual flames and patches range in ‘bulk’ com- east, and Langangen Fault, west) (Fig. 3; Heldal position from alkali feldspar compositions, close et al. 2008). These two faults follow the general pat- to sanidine, towards albite and/or anorthoclase tern of the Oslo Graben and the structures divide the and/or pure compositions. Flames and larvikite complex into three blocks, which have dif- patches with iridescence are composed of micro- ferent potential for natural stone deposits (Fig. 4). scopic to sub-microscopic lamellaes of two phases of feldspars. The feldspars in the larvikites have Mineralogy bulk compositions containing significant propor- tions (.5%) of Ab, Or and An. Feldspars of this Larvikite is generally a coarse-grained, grey to composition are sometimes referred to as meso- bluish plutonic rock predominantly consisting of perthites, but here we prefer the more general term tabular to prismatic feldspar crystals. They are gen- ternary feldspars. As pointed out by Ribbe (1975), erally composed of 80–95% feldspar, 1–5% Ca- this composition causes instability in the crystallo- rich pyroxene, 1–5% amphibole, 0–5% , graphic structure and leads to exsolution similar to 1–5% Fe–Ti oxides, 1% apatite, 1–5% biotite, that in alkali feldspars. The bright optical interfer- +1–5% nepheline, +1–5% quartz and the acces- ence colours (iridescence) seen in certain varie- sory minerals zircon, baddeleyite (ZrO2) and ties of larvikite are due to optical refraction in the sphene. Quartz occurs interstitially in the larvikites exsolution pattern of alternating orthoclase and of the northeastern part of the area while nephe- anorthite15–18 lamellae. The intensity, as well as line takes over from quartz in the central to north- the colour of the iridescence depends on the spac- western part (Fig. 2). The bulk composition of ing and geometry of the lamellae, and generally iri- the feldspars are ternary (Barth 1945), with com- descence occurs when the thickness of lamellae is ˚ position in the range An4–30Ab58 – 82Or3–35 (Ofte- within the range of 500–1000 A. dahl 1948; Muir & Smith 1956; Smith & Muir Another kind of variation is in the distribution of 1958; Rosenqvist 1965; Nielsen 2007). In the iridescence within single feldspar crystals, and three Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 3. Aeromagnetic map of the central larvikite area, displaying ring structures and two major fault structures.

main groups can be defined: patchy (irregular Commercial sub-types of larvikite patches within each crystal), homogenous (within a crystal) and zoned (see Fig. 5). Partly, we can In the northwestern part of the area, close to the see a tendency where the younger larvikites (such town of Tønsberg, red larvikite is found (Fig. 6). as the ‘Blue Pearl’ subtype) contain predominantly This variety was named Tønsbergite by Brøgger patchy iridescence patterns, whilst some of the (1898). However, field observations suggest that older (such as the Emerald Pearl subtypes) more this variety is actually hydrothermally altered larvi- commonly have homogeneous or zoned iridescent kite (oxidized), displaying a gradual transition to crystals. grey and bluish varieties. Tønsbergite only occurs Planar alignment of the feldspars is a wide- close to the northern margins of Rings I and II spread feature of the larvikites, and of great impor- (Fig. 2) in what Petersen (1978) defined as a chilled tance in quarrying. The alignment plane represents margin zone. No production takes place in the area both the primary splitting direction of the larvikite at present time. (‘primary cleavage’ or ‘rift’) and the plane along Abandoned quarries in porphyritic varieties are which the blocks should be cut in order to maximize found further to the south at Nøtterøy (southern the visible iridescence on finished slabs. Its strike part of Ring II) and in a light-grey type at Tjøme follows the ring structures, and the dip varies from (Ring III). The Kjerringvik subtype defines most about 408 towards the north to vertical. In certain of the area named Ring IV by Petersen (1978) areas where both modal layering and planar align- (Figs 2 & 6). It consists of quite homogenous light- ment can be seen, they are subparallel or slightly grey larvikite with weak iridescence. In its eastern oblique to each other. part, magmatic layering is commonly seen. There Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 4. Map of larvikite subtypes based on new field mapping and geophysical data (From Heldal et al. 2008). are a few abandoned quarries in this subtype, but it the former variety is by far the most valuable. is considered to be of minor importance to future There are large, potential reserves of this subtype exploitation. beneath the farmland between Larvik and Sandef- Several thin zones of dark and relatively fine- jord, but so far we have little information about grained (most grains smaller than 1 cm) larvikite the quality. Minor occurrences, although hardly of are found along the western margin of the Kjerring- commercial value, are found west of Larvik. vik subtype. These are collectively named the The Sta˚laker subtype is light coloured with Bergan subtype. Blue iridescence can be seen in bluish iridescense and has generally a higher con- the feldspars, but it is not the most distinct feature tent of mafic minerals than other light-coloured of the rock. The last quarry in this sub-type was subtypes. There are a few large quarries in this recently closed. subtype, marketed under the commercial name The Kla˚stad subtype (also called ‘Emerald ‘Marina Pearl’. A zone of heterogenous larvikite Pearl’) is one of the most attractive larvikite var- southwest of Larvik is also difficult to exploit on a ieties. Quarried since the 1880s, it is one of the modern industrial scale, although it was in this darkest varieties of larvikite, and iridescence zone that the first quarrying was initiated in the varies from dark blue to silver/bronze, of which early 1880s.

Fig. 5. Iridescence in larvikite crystals (20 mm in size). Homogenous (left), patchy and zoned (right). Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 6. Subtypes of larvikite that have been or are in production. Those marked with blue text are being produced at present time.

In addition to the Kla˚stad subtype, the light- of the feldspar crystals, recent innovation on surface coloured Tvedalen subtype (‘Blue Pearl’), display- treatment has improved the visual performance of ing strong, blue iridescence, is the best known and rough surfaces: the ‘caress’ process polishes the at present the larvikite sybtype with the highest high spots of the slab and leaves the lower areas to production rates. Although this subtype can be fol- a high hone. Waterjet treatment leaves a spalled lowed laterally for almost 20 km, only the present surface similar to heat treatment (flaming) but quarry area in Tvedalen has been proven to contain with a high gloss. Thus, the unique character of lar- homogeneous quality larvikite in sufficiently large vikite may be displayed in a wider range of appli- volumes to secure long-term sustainable production. cations than before. The areas just south of and north of Tvedalen are Although the different subtypes of larvikite dominated by light-coloured larvikite with slightly have almost the same mineral content, there are weaker and more silvery iridescence, named the some differences in durability and physical proper- Bassebu–Prestskjeggen subtype, of which there ties within the area. Generally, the light-coloured might be future potential for exploitation. larvikite with the smallest grain size has the best The Malerød subtype (commercial name ‘Royal technical properties (Table 1). Light-coloured larvi- Blue’) was introduced commercially as late as in the kite with large grain size (Malerød subtype) has 1970s and the area has subsequently become an slightly lower compression and flexural strength important production site. It is coarser grained and slightly higher porosity and water absorption. than other light-coloured larvikite types and dis- The dark larvikite (Kla˚stad subtype), also with plays bright blue iridescence. The subtype can be large grain size, displays the weakest properties followed both to the east and west of the present regarding strength and water absorption (Table 1). production area. For this reason, the subtype is less recommended for facade cladding than the others. Quality of larvikite The role of the grain size is partly linked to the shape of the feldspar grains; straight grain bound- Larvikite has a wide range of uses, from outdoor aries are more common in the subtypes containing paving and cladding of skyscrapers to table tops the largest feldspar grains. This texture facilitates and sculptures. Whilst polishing or honing previ- intergranular micro crack formation, leading water ously were necessary for displaying the iridescence along the grain boundaries and thus exposing Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Table 1. Physical properties of larvikite*

Property Standard Tvedalen Malerød Bassebu Sta˚laker Kla˚stad subtype subtype subtype subtype subtype

Compressive strength ns-en 1926 (mpa) 231 226 222 233 185 Flexural strength ns-en 12 372 (mpa) 14.8 11.5 16.2 14.4 11.5 Abrasion resistance ns-en 14 157 (mm) 16 16 17 16 16 Open porosity ns-en 1936 (%weight) 0.1 0.2 0.1 0.1 0.4 Water absorption ns-en 13 755 (%weight) 0.04 0.08 0.04 0.04 0.14 Apparent density ns-en 1936 (Kg/m3) 2730 2730 2760 2720 2700

*Note difference between dark larvikite (Kla˚stad subtype) and Malerød subtypes to the others. Data from fact sheets, Lundhs (www. Lundhs.no). deteriorating minerals such as olivine (and nephe- (Fig. 7). Many of the stone churches in the region line in the light coloured varieties) more easily to are made of larvikite. Although erratic blocks were chemical weathering. Thus, staining of iron hydrox- applied in some cases, some churches display evi- ides (from olivine) and ‘patchy’ clay formation dence of more organized quarrying and manufac- (from nepheline) may be the result when used out- turing, in particular regarding the red ‘Tønsbergite’ doors in humid climate, for instance. variety of larvikite (Brendalsmo & Sørensen 1995). It took several hundred years until larvikite again came on the agenda. In the 18th century, the Danish- Production and use Norwegian king initiated a hunt for ornamental Historical significance stones – or ‘beautiful marbles’ – in Norway (Jansen & Heldal 2003). The iridescent larvikite The first recorded use of larvikite as dimension and was known to scholars at that time, and a letter ornamental stone dates back to the 12th century from 1811 stated that exploitation of larvikite for

Fig. 7. Medieval larvikite capitel from Tjølling church. Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 8. Larvikite quarries (small circles) as described by Oxaal (1916).

ornamental stone was a ‘patriotic task’ (Oxaal followed, and based on advice from Theodor 1916). However, the Napoleonic wars did put a pre- Kjerulf, the first director of the Geological Survey liminary end to such dreams. Norway came out of of Norway, quarries in the beautiful dark larvikite the war in union with Sweden. A new royal castle started in 1888. In the early 20th century, the pro- was constructed in Oslo during the 1820s, and red duction had reached a significant size and involved larvikite was applied in the foundation walls, many quarry areas (Figs 8 & 9; Oxaal 1916). marking the first large-scale use of the rock in the Export of larvikite took many different ways. modern period. Kessel & Ro¨hl brought the larvikite blocks to Small-scaled production carried on throughout Sweden for further processing for funerary monu- the 19th century, mainly for funerary monuments ments. These were re-exported to Germany under and foundation walls (Horn 2002). In 1878, a the name ‘Labrador aus Schweden’. The company quarry at Nøtterøy delivered dimension stone to also introduced larvikite in many impressive build- buildings in the town of Tønsberg (Børresen & ings in Germany during the late 19th century. Heldal 2009). Before the turn of the century, larvikite was well From about 1875 to 1895, Norway suffered an introduced to the USA market. Through the stone economic depression, which among other things workshops in Aberdeen, larvikite (often paired led to a massive emigration, first of all to the with red Swedish ) found the way to fashion- USA. But this was also a time for exploring new able buildings in London and other British cities, opportunities. The farmer Ferdinand Narvesen was and due to the extensive use in London pubs, larvi- the first to see the potential of exporting larvikite. kite got a new nickname – ‘Pubstone’ (Fig. 10). He started a quarry at Fuglevik near the town of Larvikite rapidly gained a solid position in Nor- Stavern in 1884 (Oxaal 1916). Two years later, lar- wegian architecture; from fashionable ‘boutique’ vikite won a gold medal at the world exhibition facades (Fig. 11) to massive, Art Nouveau buildings in Liverpool. This made other investors and com- clad with Scottish rubble (Fig. 12). In Norway and panies see the large potential in larvikite produc- abroad, larvikite became a symbol of fashion and tion. The German company Kessel & Ro¨hl was the wealth. Many banks did use larvikite around their first to establish regular export of larvikite. Many entrances, so did Harrods in London and Galleries Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

GLOBAL STONE HERITAGE: LARVIKITE, NORWAY 29

Fig. 9. Quarrymen releasing blocks with long wedges. From Oxaal (1916).

Lafayette in Paris. Innovative architects used larvi- After a short period of depression in the early kite, as for example in some of the most well-known 1930s production in the quarries was back on track Art Deco buildings in London (Fig. 13). when the second world war started. During the

Fig. 10. London pub with bluish larvikite and red, Swedish granite on the facade. Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 11. Larvikite and fashion have always worked well together. Shop in Oslo, Norway.

Fig. 12. Massive architecture in Scottish rubble – the previous headquarter of the National Bank of Norway (built in 1907). Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

GLOBAL STONE HERITAGE: LARVIKITE, NORWAY 31

Fig. 13. Cunard House, London. Art Deco in larvikite (built in 1930).

German occupation of 1940–45, stocks of larvikite After the war, modernistic architecture did put blocks were built up, intended for use in Hitler’s some limits to the use of larvikite. The rock was victory monuments. For obvious reasons, these more popular abroad than in Norway, and in the fol- remained in the quarries. lowing decades, larvikite was gradually spread Since the beginning of the modern period pro- throughout the world and became global. duction, a significant part of the larvikite has been applied for gravestones and funerary monuments. Modern production Already in the last quarter of the 19th century, gravestones were exported to Germany and the After a long period with artificial building materials British Isles. At the present time, larvikite can be and ‘brutalistic’ architecture, a renaissance for natu- seen at funerary sites all over the world (Fig. 14). ral stone came with the 1980s. The natural stone Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Fig. 14. Many celebrities rest under a slab of larvikite.

Fig. 15. Diamond wire sawing in a modern larvikite quarry. Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

GLOBAL STONE HERITAGE: LARVIKITE, NORWAY 33 industry boomed in the last half of the decade, the world. Today, we may see the stone in almost including the larvikite industry. New quarrying every city in the world. Its widespread use, as well technology, diamond wire sawing in particular as the application in many important pieces of archi- (Fig. 15), combined with growing global markets tecture and monuments, indeed make larvikite a made the industry profitable and modern. Larvi- rock of global importance; a unique rock from a kite blocks were exported globally, but most of unique geological setting. them to Italian stone processing industries, who re-exported finished products. Larvikite was applied in a number of high- prestige buildings throughout the world, such as References Devon Tower, Calgary (constructed in 1988), Barth, T. F. W. 1945. Studies on the Bank of America tower, Jacksonville (1990), the Complex of the Oslo Region II. Systematic petrogra- Jame Asr Hassanil Bolkiah mosque in Brunei phy of the plutonic rocks. Det Norske Videnskaps- (1992) and the seven star hotel Burj-Al-Arab in Akademi i Oslo, Skrifter. Dubai (1999). The financial crisis in 2009 caused Beard, L. P. 1999. Data acquistion and processing – a temporary decline in the larvikite production, but Helicopter geophysical surveys, Larvik, 1998. NGU after some adjustments and restructuring of the Report 99.026. Brendalsmo,A.J.&Sørensen, R. 1995. Kvader i industry, the production is now as large and effi- Sentrum. Ha˚ndverksmessige og geologiske forutset- cient as ever, although the prices are not so high ninger for bygging av steinkirker i Vestfold i tidlig as before and the export centre of gravity shifted middelalder. Hikuin, 22, 77–94. from Italy to China. At present, the main quarry Brøgger, W. 1890. 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Geology for scale does indicate a promising future for pro- Society. NGU, Special publications, 11, 5–18. duction. At the same time, the need for displaying Jansen,Ø.&Heldal, T. 2003. Marmor fra de Lil- the history of the larvikite production to the public lienschioldske marmorværker i de danske slottsanlegg. ˚ becomes important. Some quarries are protected as In: Arbok for Bergen Museum 2002. Bergen Museum, heritage sites, and others are included in natural Bergen, 52–58. Larsen,B.T.&Olaussen, S. 2005. The Oslo Region. A protection areas. study in classical Palaeozoic geology. Field guide to NGF’s Centennial field trip, May 26–28. Mogaard, J. O. 1998. Geofysiske ma˚linger fra helikopter Concluding remarks ved Larvik, Vestfold, teknisk rapport. NGU Report, 98.021. The production and use of larvikite have a long Muir,I.D.&Smith, J. V., Jr. 1956. Crystallization of history in Norway. However, the industrial history feldspars in larvikites. Zeitschrift fu¨r Kristallographie, from 1884 onwards is first of all a story about the 107, 182–195. Neumann gradual globalization of larvikite as dimension and , E. R. 1978. Petrogenesis of the Larvik ring- complex in the Permian Oslo Rift, Norway. In: ornamental stone: for buildings, grave monuments Neumann,E.R.&Ramberg, I. B. (eds) Proceedings and art works. Larvikite became important in a of the NATO Advanced Study Institute, Paleorift Sys- European and American context in the late 19th tems with Emphasis on the Permian Oslo Rift, Oslo, and early 20th centuries. Since World War II, the Norway, July 27–August 5, 1977, Volume 1. D. Reidel use of larvikite gradually spread out to the rest of Publishing Company, Dordrecht, Holland, 231–236. Downloaded from http://sp.lyellcollection.org/ by guest on April 29, 2015

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Neumann, E. R. 1980. Petrogenesis of the Oslo Region The Oslo Paleorift. A Review and Guide to Excursions. larvikites and associated rocks. Journal of Petrology, NGU, Trondheim, 337, 163–182. 21, 499–531. Oxaal, J. 1916. Norsk granit. Norges geologiske undersø- Neumann, E. R., Brunfelt,A.O.&Finstad,K.G. kelse, 76. 1977. Rare earth elements in some igneous rocks in Petersen, J. S. 1978. Structure of the larvikite-lardalite the Oslo rift, Norway. Lithos, 10, 311–319. complex, Oslo Region, Norway, and its evolution. Neumann, E. R., Tilton,G.R.&Tuen, E. 1988. Sr, Nd Geologische Rundschau, 67, 330–342. and Pb isotope geochemistry of the Oslo rift igneous Ribbe, P. H. 1975. Exsolution textures in Ternary and Pla- province, southeast Norway. Geochimica et Cosmochi- gioclase Feldspars; interference colors. In: Ribbe,P.H. mica Acta, 52, 1997–2007. (ed.) Feldspar Mineralogy. Mineralogical Society of Nielsen, A. M. 2007. En petrologisk og geokemisk America, short course notes, 2, 241–270. undersøgelse af ringintrusionerne IV og V i larvikit- Rosenqvist, I. T. 1965. Electron-microscope investi- komplekset Norge. Master thesis. University of gations of larvikite and tønsbergite feldspars. Norsk Aarhus, Denemark. geologisk tidsskrift, 45, 69–71. Oftedahl, C. 1948. Studies on the igneous rock complex Smith,J.V.&Muir, I. D. 1958. The reaction sequence in of the Oslo Region. IX. The feldspars. Det Norske larvikite feldspars. Zeitschrift fu¨r Kristallographie, Videnskaps-Akademi i Oslo, Skrifter. I. Mat.-Naturv. 110, 11–20. Klasse, 3. von Buch, L. 1810. Reise durch Norwegen und Lapland. Oftedahl,C.&Petersen, J. S. 1978. Southern part of Ordentlichen Mitgliede der Ko¨niglichen Academie der the Oslo Rift. In: Dons,J.A.&Larsen, B. T. (eds) Wissenschaften zu, Berlin.