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Keivy
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The western Keivy mountains are most famous for a classic Kola specimen, the staurolite cross. The Keivy massif consists of Archaen gneiss of the Keivy block or Keivy terrane. But saying Keivy is metamorphic rock with staurolite only would be way to simple. There are numerous interesting intrusions inside the Keivy terrane. Mount Ploskaya's bluish green Amazonite is only one example.
Berjozovaya is known as an almandine-muscovite locality. Should be metamorphic
mineralogy
Almandine Muscovite
A granite-pegmatite alike the better known Ploskaya, but seems to be far less exciting.
mineralogy
Almandine, Amazonite, Quartz and Muscovite.
mineralogy
Almandine Muscovite Sillimanite
The Panski massif is a gabbro-norite intrusion, just between the Keivy terrane and the Imandra-Varzuga rift belt. It borders the Belaya Tundry massif, mentioned above. Fiodorovo is a locality within the Panski massif Apparently Panski Tundry is PGM bearing. There should definitely be more interesting minerals there!
mineralogy
Kotulskite and Vysotskite
geology
Parushnaya is one of the many amazonite pegmatites of the Western Keivy. The
pegmatite os located in biotitegneiss.
mineralogy
Albite Biotite Fluorite Fluoroapatite Galena Microcline Oligoclase Quartz Zircon
Amazonite
Ploskaya
(Ploskogorskoye deposit)
If you are ever lost looking for this hill on Kola, look for a flat hill, because that is what Ploskaya means. Ploskaya is the best known locality in the Keivy mountains. It is best known for it's Amazonite, but the more systematic collectors will know this site for the rare yttrium mineralogy. The people who like oddities will know Ploskaya for the lead mineralogy or the fairly big bismuth crystals. Ploskaya is an alkaline granite intrusion. Bayanova dated zircons from postmagmatic albitites and came up with 1682 +/- 35 Ma, which is roughly the age of the intrusion itself.
mineralogy
Albite Anglesite Bastnasite-(Ce) Bastnasite-(Y) Bismite Bismuth Bismutite
Caysichite-(Y) Cesstibtantite Churchite-(Y) Clinophosinaite Fluorite
Fluorthalenite-(Y) Gadolinite-(Ce) Gadolinite-(Y) Hingganite-(Y) Hingganite-(Yb)
Holtite Iimoriite-(Y) Kainosite-(Y) Karibibite Keivyite-(Y) Keivyite-(Yb)
Kingsmountite Kuliokite-(Y) Lanarkite Leadhillite Manganocolumbite Meliphanite
Microcline Microlite Plumbomicrolite Plumbopyrochlore Polylithionite Quartz
Sillenite Stibiotantalite Tengerite-(Y) Thalenite-(Y) Thorite Vyuntspakhkite-(Y) Wulfenite
Xenotime-(Y) Zinnwaldite Zircon
 Bismuth |
 Churchite-(Y) |
 Hingganite-(Y) |
 Keivyite-(Yb) |
 Kuliokite-(Y) |
 Vyuntspakhite-(Y) |
Bayanova et al, 2001, U-Pb Dating of Zircon Megacrysts (8cm) from Amazonite Rand =pegmatite of Mt. Ploskaya, Baltic Shield.
Rovgora
(Rovozero)
Rovgora is a granite pegmatite, which gained fame in the mid 1990's for the unusual paragenese of Astrophyllite, which occurs here as inclusions in quartz.
mineralogy
Aeschynite-(Y) Albite Astrophyllite Fergusonite-(Y) Gadolinite-(Y) Genthelvine
Ilmenite Microcline Quartz
The Sakhariok massif is a 2613 Ma old nepheline syenite. There is also a slightly older alkaline syenite phase present. Around the intrusion is a fenite zone.
mineralogy
Bastnasite-(Ce) Britholite-(Ce) Britholite-(Y) Chrysoberyl Meliphanite Nepheline
Phlogopite Rhabdophane-(Ce) Zircon
geology
Semyatrovye is one of the 27 known Kyanite localities in the Keivy mountains
mineralogy
Kyanite
Serpovidnyi ridge
mineralogy
Gadolinite-(Y) Kyanite Microcline Milarite Sillimanite
geology
Shuururta is one of the many Kyanite deposits in the Keivy mountains. It
consists geologically of Archean Kyanite-Staurolite schist.
mineralogy
Kyanite Staurolite
Uzkaya river
mineralogy
Hydroastrophyllite
A locality close to and very similar to Ploskaya. It is also a granite intrusion, famous for it's amazonite pegmatite.
mineralogy
Aeschynite-(Y) Albite Bastnasite-(Ce) Britholite-(Y) Chevkinite-(Ce) Fergusonite-(Y)
Fluorite Gadolinite-(Ce) Keivyite-(Yb) Magnetite Microcline Vyuntspakhkite-(Y)
Xenotime-(Y)
geology
Yelozero is another granite pegmatite containing Amazonte and REE minerals
mineralogy
Allanite-(Ce) Anatase Cassiterite Epidote Galena Microcline Rowlandite-(Y)
Thalenite-(Y) Thorite Yftisite-(Y) Yttrialite-(Y) Zircon
It is an alkaline syenogranite with an age of 2674 m.y. 'Zapadnokeivy' means 'western Keivy'. I'm not sure all minerals on the marked labeled as 'western Keivy' (Staurolite, Amazonite and Kyanite) really come from this intrusion.
references:
Archaen A-type Granitoids and related rocks of the Kola Peninsula,
Russia. by prof Nelson Eby et al
Archaen to paleozoic mantle plumes in the N-E baltic shield. by T. Bayanova
