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Geological Sketch Map of the Aktyuz licensed area
1 – Quaternary sediments; 2 – Middle Paleozoic rhyolite; Precambrian metamorphic rocks: 3 – schist and amphibolite of Paleoproterozoic Kuperlisai Formation; 4 – gneiss of Archean Aktyuz Formation; Permian-Triassic intrusive rocks: 5 – granophire; 6 – subalkali leucogranite of the Kuperlisai pluton; 7 – syenite; Middle Paleozoic intrusive rocks: 8 – diorite and quartz diorite; 9 – granodiorite and granite; Precambrian metabasic rocks: 10 – amphibolite and gabbro-amphibolite; 11 – metagabbro and metadiabase; 12 – postmineral quartz lenses; 13 – faults; 14 – section line; 15- Aktyuz licensed area contour.
Major faults (letters on the map): (A) West Kuperlisai, (B) East Kuperlisai, (C) Kutessai, (D) Cholonsai, (E) Anjilga, (G) Aktyuz-Karabatnak, (L) Rudny, (K) Kvartsevy, (M) Yuzhny, (N) Sienitovy.

Ore deposits and prospects (numerals on the map): (I) Kutessai-I, (II) Kutessai-II, (III) Kutessai-III, (IV) Kuperlisai, (V) Kolesai, (VI) Aktyuz, (VII) Anjilga.

“A qualified person has not done sufficient work to classify the historical estimate as current mineral resources, Stans Energy Corp. is not treating the historical estimate as current mineral resources and the historical estimate should not be relied upon.” Dr Gennady Savchenko QP for Stans Energy Corp., and managing Director for Stans Energy KG.

Translated from Russian

There are more than 20 areas of Lead-Zinc, Tin, Thorium, Rare Earth, Copper and Molybdenum mineralization within the Aktyuz licensed area. Among them Aktyuz, Kutesai-II, Kuperlisai and Kalesai have mining potential.
All the known areas related to the following genetic types despite their age and relation to some magmatic cycle:

  1. Scarn (magnetite scarns, scarns with scheelite and zones of intensive rock epidotization).
  2. Pegmatite (thorite pegmatite).
  3. Pneumatolite (feldspar-tourmaline-fluorite-magnetite manifestations, rare-earth and rare-metal greisens, hornfelses and others).
  4. Hydrothermal (polymetallic, arsenopyrite, pyrrhotite, chalcopyrite manifestations; rare-metal, rare-earth mineralization and many others).

Two last stages have the most practical potential and they are genetically connected with Permian intrusive complexes.

Aktyuz licensed area is studied in detail at the surface and new deposit discoveries will be hidden ore bodies and the deposits detection using geophysics and geochemical methods will have an overlapping corelation. Zirconium-Thorium minerals increasing as well as Bismuth and Silver concentration increasing tendency are noted with depth at the deposits of the Aktyuz licensed area.

Aktyuz deposit rests among green amphibole shales near the contact with paragneisses in the form of a steeply dipping mineralized almost vertical granophyres pipe bordered by biotite hornfelds and brecciated green amphibole shales. The Aktyuz pipe is traced for 400 m with lateral dimensions up to 80m to 120m. The mineralization (lead-zinc) is mainly concentrated in the upper part of the pipe, gradually wedging out (bottoming) with depth. The ores material composition is complex. The following ore minerals are found in Aktyuz; galena, sphalerite, molybdenite, cassiterite, arsenopyrite, magnetite, hematite, ferritorite, monazite, xenotime, chalcopyrite and others.

The deposit was developed for polymetallic raw materials, and it had been fully mined by 1960. The deposit mining was made fron underground.

The deposit was mined in Lead delineated blocks (Lead cut-off grade is 0.7%) to the point of 2,293 m, Lead reserves were not detected below this mark. Aktyuz rare earths ores average grade is 0.15-0.50% and it does not decline with depth.

Kutessai-II deposit is localized in pipe-shaped granophyres bodies of the Upper Permian intruding Upper Proterozoic green amphibole shales.

The ores are mainly complex: REE, Zirconium, Thorium, Lead, Zinc, Silver, Bismuth, Molybdenum. The main rare-earth minerals are monazite, xenotime, yttrobastnaesite, yttroparisite, yttrosynhisite, yttrofluorite, fluocerite, cyrtolite, ferritorite, malacon.

Specific zoning of mineralization distribution is revealed at the deposit: polymetallic and rare earth mineralizations develop in the upper (apical) part of granophyres pipes, rare earth mineralization – in the middle part and zirconium-thorium-rare-earth mineralization – in the lower part. Eight rare-earth ores types are defined: quartz-chlorite, quartz-sericite, pink granophyres, quartz-muscovite, biotite hornfelses, brecciated shales, silex metasomatites and silicified rocks of secondary quartzite type. The first three types represent 80% of all the rare-earth metal reserves and they have higher concentration rates.

The Northern “blind” ore body was revealed with Rare Earths, Thorium, Zirconium and other accompanying components high grades as the result of Kutessai-II exploration. Mineralization continuation to the depth was set with Zirconium, Thorium, Hafnium, Tantalum and Niobium higher grades.

Kutessai-I deposit is located at the south-eastern flank of Kutessai-II deposit and represented by small mineralized granophyres pipe (30 by 60 m) and quartz bodies. In recent years, using the Kutessai-II exploration data, it was found, that Kutessai-I granophyres transform with depth into pipe body representing the Kutessai-II granophyres pipe apophysis and link with it at the point of 2,428 m. Kutessai-I ores are represented by the following minerals: galena, sphalerite, REE, pyrite, chalcopyrite, siderite, arsenopyrite, molybdenite and other minerals similar to Kutessai-II and Aktyuz deposits.Kutessai-I ores are fully mined to the point of 2,413 m in the Kutessai-II open-pit delineation block and stored in the special ore stock. They were investigated in order to obtain industrial concentrations of rare earths and accompanying components.

The deep horizons of this object are planned to be explored for rare-earth elements in conjunction with Kutessai-II exploration.

Kutessai-III deposit is located at the left slope of Kutessai valley representing Kutessai-II south-western flank continuation, lying 0.5 km far from it. This zone is coposed of small groups of separated ore bodies detected in surveying (1945-1946) and exploration (1957-1961) with Molybdenum and Thorium mineralizations. The deposit absolute mark is 2,450 m. Morphologically ore occurrence is composed of some separate lenses (with thickness from 2-3 m to 35 m) drawn to the north-east. Useful components grades: Rare Earths – 0.15%, Molybdenum – 0.03-0.04%, Lead – 0.09-0.15%, Zinc – 0.05%, Copper – 0.01%.
(See footnote 1)

Kuperlisai deposit is located at the Kuperlisai river right bank, south-west 1 km away from Kutessai-II deposit. The deposit is composed of deeply metamorphosed Pre-Paleozoic shales and paragneisses intruded by diorites, syenites and alaskite granites.

Alaskite granites are traced in the forms of two tongue-shaped bodies north-east steeping under green amphibole shales and paragneisses. Alaskite granites are represented by aplite type transformed into quartz-sericite rocks and greisens by post-magmatic processes. The mineralization is localized in quartz-sericite rocks taking mostly the apical part of the alaskite Massif.

The following ore minerals are set: ferritorite, zircon, cyrtolite, monazite, xenotime, magnetite, cassiterite, arsenopyrite, molybdenite, galena and others. All the ore minerals are characterized by low grades and do not form ores with the exception of the rare-earths.

Kuperlisai Rare-earths average grade is 0.20%, mineralization scope is 80 m from the surface middle point to the lowest explored horizon. The northern endo- and exocontact parts of greisens and greisenized rocks on granites with green amphibole shales contain rare earths up to 0.5%. Rare earths grade reaches 1.53% at the area of breccia tubular body development cemented with albite. A 0.12-0.14% higher concentration of rare earth elements (adit 17) is found at the north-eastern part of the Massif where granites steep under gneisses close to the contact with green amphibole shales.

Kalesai deposit is located on the right slope of the Kalesai river, south-west 0.5 km away from Aktyuz deposit. The mineralization is represented by Beryllium minerals (phenakite, bavenite), galena, pyrite and chalcopyrite in quartz-feldspar vein and host green amphibole shales. Structurally the deposit is classified as stockwork type.

Kalesai deposit was explored in detail as the object of Beryllium mineralization to the depth of 150 m by underground exploration drifts and drill holes. The deposit C1 proven reserves were confirmed by USSR SRC in 1971. The main ore zones reserves were partly explored with the Aktyuz polymetallic deposit exploration before the Kalesai exploration and together with the Kutessai exploration. Mined ore is stored for the possible future usage despite what was considered non-economic reserves in 1991.

Anjilga mineralization is located on the right slope of Anjilga-Sai river north-east 1.7 km away from Aktyuz deposit. In 1971, three large geochemical anomalies were revealed here (V.F. Kim at al.). The exploration exposed polymetallic and rare-earth mineralization confined to folded and brecciated paragneisses. The ore mineralization is represented by cerussite, wulfenite, galena, fluorite, cassiterite. Pyrite, apatite are common and fluorite is rare. Paragneisses, large fragmental brecciation and great amounts of latitudinal, meridional and north-east tectonic faults are noted at the deposit. Porphry veins are traced in a latitudinal direction. Anomaly I and anomaly II geological structure and material composition similarity to the Aktyuz and Kutessai-II upper horizons is favorable sign for alaskite granite hidden (“blind”) orebody and related industrial rare-earth mineralization is evident.

The Aktyuz orebody produced 57,380 tones of lead, 149.4 tons of tin, 1744.8 tons of zinc, 388.9 tons of molybdenum, 13.417 tons of silver, 769.6 tons of copper and 5.344 tons of gold and 3820 tones of REE.

The average mined lead grade of the Aktyuz orebody was 5.02% with zones of up to 40% lead.

The Kutessay II ore body produced, 23,286.9 tons of REE, 21099 tones of lead, 167 tones of molybdenum, 17.276 tones of silver and 25.065 tones of bismuth.

The average mined grade of Kutessay II was 0.41% REE with zones up to 30 to 40 % REEs.

Therefore, the above mentioned facts let us recommend rare-earth and other elements prospecting at the deep horizons of Kutessai-II, Kutessai-III, Aktyuz, Kuperlisai deposits and Anjilga mineralization zone in order to transfer prognosticated resources to economic reserves.

The Kutessai southern and south-eastern flanks are worth prospecting and blind ore bodies with industrial grades of Rare Earths, Molybdenum, Bismuth, Thorium and other useful components can be revealed there. Watershed area between Kuperlisai and Kutessai is also perspective for deep survey and prospecting.

Many geological authors note that small mineralization zones are of great interest as indicators for “blind” ore bodies even though they have non-economic values at the surface.

Geochemical, EM, Mag, Gravity, IP and radiometric surveys can identify the presence of orebodies as the signature of the known orebodies respond to all of these exploration methods.

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