Here you will find short notes about on-going projects related to the mineralogy of the syenite pegmatite minerals in the Oslo Region.
 
 

The minerals from the syenite pegmatites in the Oslo Region, Norway: the book

I started working on this book 20 years ago. With ups and downs the project has steadily grown by collection of data, photos and informations, making new chemical analysis of a lot of minerals, checking and re-checking old informations, writing and re-writing the draft, re-drawing many of Brøgger’s crystal drawings in modern crystallographic setting, plus making new crystal drawings. The first chapters cover the geology of the region and the pegmatites, descriptions of the most important localities, as well as the history of the more than 200 years of investigation on the syenite pegmatites. Then follows descriptions on all the 175 minerals found in the syenite pegmatites, including data on the crystallography, chemical compositions (including new and unpublished analytical data), physical and optical properties, occurrences and paragenesis. The book will contain a lot of new and unpublished photos, including many SEM photomicrographs.
 
 

Calcio-ancylite-(Ce)

A few years ago, calcio-ancylite-(Ce) was found in the Tuften larvikite quarry, Tvedalen, in a recently blasted, small syenite pegmatite. The mineral occurred in small cavities which was actually moulds after fluorapatite crystals, and calcio-ancylite-(Ce) was obviously the result of hydrothermal alteration of the apatite. A paper on the calcio-ancylite-(Ce), its apatite precursor, and the occurrence is now under construction and nearly finished.
 
 

UK-5, a new mineral in the ganophyllite-bannisterite group

It is now more than 25 years since the mineral was found on the dumps from the water tunell at Valleråsen, Porsgrunn, and was identified as a mineral in the ganophyllite-bannisterite group. An attempt on solving the crystal structure is now a success thanks to Drs. E. Ferrow and X. Zou at the Universities of Lund and Stockholm, respectively. A paper on the mineral is under construction.
 
 

UK-7, a calcium-rich member of the gadolinite group

At two occations, in two different syenite pegmatites, a calcium-rich member of the gadolinite group has been found in the Tuften by my good friend Ingulv Burvald. Unfortunately, the minerals were metamict amorphous, and this has hampered the investigation. Recrystallization in air expells CeO₂ from the crystal structure. An attempt on recrystallization under hydrothermal conditions will be tried.
 
 

UK-10, a "new" Be-OH-silicate mineral

This mineral occurs in vugs as small, white to beige, tiny spherulites on hambergite crystals. A preliminary study shows that the mineral is an hitherto non-valid species, previously described from Russia. The mineral is a hydrous beryllium silicate. Due to the small amounts available, the tricky chemistry and the lack of single crystals, the mineral is a challenge to investigate. My intention is to re-validate the mineral.
 
 

Götzenite and rosenbuschites

Götzenite (previously called UK-6) and rosenbuschites from from the Langesundsfjord district are currently being investigated chemically and structurally by Ph. D. candidate Claes Christiansen, Geological Museum in Copenhagen. Christiansen has during the last three years published papers on the crystal structure of kupletskite, and on the relationship between the crystal structures of götzenite and rinkite. He has also been a co-author in the paper on nafertisite from the Nanna pegmatite, South Greenland.
 
 

Astrophyllite group minerals

Paula C. Piilonen is a Ph. D. candidate at Ottawa-Carleton Geoscience Centre in Ottawa, Canada, and is working on a thesis regarding the crystal chemistry and paragenesis on astrophyllite group minerals from over-saturated and under-saturated alkaline intrusions. Several astrophyllite group minerals from the Larvik plutonic complex are included in her work. Piilonen published a paper on the crystal chemistry of aegirines from Mont Saint-Hilaire in 1998, and described the new mineral niobokupletskite in 2000.
 
 

Suggestions for future projects
 

Although the mineralogy of the syenite pegmatites in the Oslo Region has been studied for more than 200 years, there are still many interesting and challenging topics to start working on. Several of the "old" minerals deserve new investigations using modern analysing techniques, and a deeper insight is needed on the "new" minerals. Here are a few suggestions for future work. Anyone is welcome to start working. If you are interested in more information about any of the points below, please feel free to contact me.

• Chemical analyses of the more common minerals such as apatite, pyrochlore, wöhlerite, biotite, aegirine and amphiboles, together with a geographical and geochemical correlation with the magmatic evolution of the plutonic complex.
• Studies on melanocerite, tritomite and "caryocerite" in order to establish their composition and alleged relationship to the apatite group minerals.
• Studies on minerals of the gadolinite group ( homilite - "erdmannite" - gadolinite) which are often found in association with meliphanite.
• Studies on mosandrite minerals in order to establish the correct relationship and nomenclature between mosandrite, rinkite and rinkolite.
• Confirmation of the chemical composition of britholites.
• Confirmation of the chemical composition of the REE minerals which have been found during the last decades, such as fergusonite, cerite, tadzhikite, allanite and kainosite.
• Studies on the luminescence phenomena (UV, CL) in leucophanites with correlation to minor element composition.
• Re-examination of "eucrasite", "calcio-thorite", and other unspecified REE-Th-rich minerals.
• Chemical analyses on catapleiites from different localities. Does calcium catapleiite exists among them?
• UK-9, probably a new Na-Mn-Zr-silicate mineral in the cuspidine group.