Jouni Laurinperä's Photo Gallery
FNV-5QPVäyrynenite BeMn2+(PO4)(OH) , Montebrasite LiAl(PO4)(OH) , Muscovite KAl2(AlSi3O10)(OH)2 , Quartz SiO2
Viitaniemi pegmatite, Eräjärvi area, Orivesi, Pirkanmaa, FinlandField of View: 12 cm
Pink väyrynenite, cream montebrasite, greenish muscovite, quartz. Also hydroxylherderite and hurlbutite in back of sample. Ilkka Mikkola collection.
0YQ-V5UPollucite (Cs,Na)2(Al2Si4O12)·2H2O
Viitaniemi pegmatite, Eräjärvi area, Orivesi, Pirkanmaa, FinlandField of View: 10 cm
Pollucite from Viitaniemi. Ilkka Mikkola Collection.
K8M-JKDElbaite Na(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3(OH) , Beryl Be3Al2(Si6O18) , Quartz SiO2
Haapaluoma pegmatite, Peräseinäjoki, Seinäjoki, South Ostrobothnia, FinlandField of View: 9 cm
Purplish elbaite tourmaline, pink beryl, smoky quartz etc. Ilkka Mikkola Collection.
G48-AX3Chalcopyrite CuFeS2 , Tennantite Subgroup Cu6(Cu4C2+2)As4S12S , Bornite Cu5FeS4 , Quartz SiO2
Kaatiala pegmatite, Kuortane, South Ostrobothnia, FinlandField of View: 400 μm
Yellow chalcopyrite, greenish-gray tennantite, tan-coloured bornite, light-bluish possible chalcocite, dark-bluish possible digenite, blackish or dark grey quartz & other silicates. Pictures hues have been darkened somewhat to improve visibility / contrast. Sample from J.Dyer.
MRF-HJ1Tennantite Subgroup Cu6(Cu4C2+2)As4S12S , Chalcopyrite CuFeS2 , Löllingite FeAs2 , Bornite Cu5FeS4 , Quartz SiO2
Kaatiala pegmatite, Kuortane, South Ostrobothnia, FinlandField of View: 650 μm
Greenish-grey tennantite with yellow chalcopyrite, bright pale löllingite, very minor dirty-brownish bornite, dark silicates and bluish-grey possible chalcocite. This sample also contains minute patches of covellite elsewhere.
Löllingite samples at Kaatiala with very small (50-150um) chalcopyrite patches would seem to be far more common than any samples containing tennantite, such as a superb polished section donated to me by I.M. Sample from J.Dyer.
KMV-JDEQuartz (Var: Chalcedony) SiO2 , Mogánite SiO2 , Quartz SiO2
Vuotso, Sodankylä, Lapland, FinlandField of View: 1.6 mm
Zoned edge area of a Vuotso area chalcedony sample collected by Jorma Valkama (GTK) many years ago. This material has varying, medium-high moganite content verified by both Raman and XRD. The thinsection is intentionally slightly overthick (>30 microns) in a few spots. A lot of the Vuotso are samples have only low moganite and fibrosity content, and / or mostly very small texturing, like several chalcedony / "moganite" samples from around the world polished and analyzed recently for reference purposes. Sample from J.Dyer.
V9T-W36Quartz (Var: Chalcedony) SiO2 , Mogánite SiO2
Kaitaselkä, Sodankylä, Lapland, FinlandField of View: 3.3 mm
Over-thick thinsection of lined or "cross-hatched" type of Kaitaselkä chalcedony, medium-low moganite content. It has been suggested, based on handsample features , inner structure and other factors that this type of material may be carbonate substituted by SiO2. There is clear Fe-oxide / hydroxide impurities in this type of material and varying degrees of interstitial "fibre circles" visible in more closeup photos in particular. Sample from J.Dyer.
H85-L1EQuartz (Var: Chalcedony) SiO2 , Mogánite SiO2 , Quartz SiO2
Kaitaselkä, Sodankylä, Lapland, FinlandField of View: 1.5 mm
An over-thick thinsection preparate of mixed-type chalcedony from the Kaitaselkä chalcedony occurence.
It has been suggested that the "lined" lower-moganite-content material is at least partially SiO2-replaced carbonate rock. Especially in cross-hatched thinsection samples there would appear to be relicts of former cleavage planes. Also, visual inspection of hand sample surface shapes display material which appears to be semi-flaky former carbonate. In some material there is also goethite with some relict pyrite. Both latter minerals have also been documented for the Kaitaselkä area during ore mineral investigations. Sample from J.Dyer.
2J2-9FJQuartz (Var: Chalcedony) SiO2 , Mogánite SiO2 , Quartz SiO2
Kaitaselkä, Sodankylä, Lapland, FinlandField of View: 0.4 mm
Highly fibrous chalcedony thinsection preparate (J. Dyer) from Kaitaselkä chalcedony occurence. Medium-high moganite content confirmed by both Raman (J. Dyer, later GTK) and XRD (GTK). Sample from J.Dyer.
LTX-YV3Quartz (Var: Chalcedony) SiO2 , Mogánite SiO2 , Quartz SiO2
Kaitaselkä, Sodankylä, Lapland, FinlandField of View: 1.6 mm
Overthick thinsection of Kaitaselkä chalcedony with banding and macrocrystalline quartz centre. Transmitted cross-polarised light. Kaitaselkä locality contains several types of chalcedony and also jasperoid type substitution material. Sample from J.Dyer.