Telkkälä - NICKEL Database

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Name	Telkkälä		DATA UPDATED	9.2.2006
Secondary names
Map sheet	313405D
Northing (kkj)	6786050		Easting (kkj)	3555450
Northing (Uni)	6786050		Easting (Uni)	3555450
Latitude	61.179109N		Longitude	28.030598E
Municipality	Taipalsaari
Nearest town	Lappeenranta, 16 km the south-east from Telkkälä
Access	500 meters from the main road 408.
Status	Closed mine		Discovery year	1961/1987
Discovery	By Outokumpu Oy. Impetus for the exploration surveys in Telkkälä was the finding of mineralised gabbro during the excavation of a cellar by a local farmer. The ore deposit was found by drilling to a geophysical anomaly, that was clearly vissible in magnetic, electromagnetic and gravity surveys.
Reservation
Exploration licence no	2077, 4111, 4546		Mining concession no	4111
Present holder	Outokumpu Mining Oy
Previous holders	Outokumpu Oy
ENVIRONMENT
Population centre
Protection areas
Water system	Lake Saimaa is about 1 km to the east from Telkkälä Ni-Cu deposit
Overburden
Hazards
Restoration
GEOLOGY
Eon	Proterozoic
Domain	Svecofennian		Province	Taipalsaari Nickel Belt
Geological setting	Telkkälä Ni-Cu deposit is hosted by a differentiated mafic intrusion composed of cummingtonite gabbro-norite-perknite outer part and peridotitic core. Small Telkkälä intrusion is located in veined migmatitic and partly schollen-migmatitic garnet-cordierite-mica gneisses. Horizontal dimensions of the Telkkälä formation, gabbro-peridotite intrusion are 50 x 150 meters and depth about 50 meters. In addition to this, there is a 200 meters long peridotite in the depth of 110–225 meters, hosting the deep ore.
Country rock	Migmatized garnet-cordierite-mica gneiss		Isotope age
Age group	Svecofennian – ca. 1.9 Ga		Deposit classification	Intrusive
Bedrock map			Geological map of the Taipalsaari area
Deformation history	Telkkälä intrusion was intruded before or during the main regional deformation and metamorphism, D2. Sulphide phase of Telkkälä intrusion was remobilised by D3 and emplaced into D3 shear structure forming the massive sulphide ore.
Metamorphic grade	High grade
Metamorphic history
Regional metamorphic mineral assemblage	garnet-cordierite±staurolite
Alteration of host rock
Alteration minerals
Post-mineralisation modifications
Structure of hosting formation	Zoned differentiated intrusion
Parental magma composition
Contamination
Depletion
HOST ROCKS
Field name	Peridotite
Modal name (Streckeisen / conventional)
CIPW-normative rock name
Modal rock name (cumulus)
Normative rock name (cumulus)
Description
Field name	Norite/hornblende-cummingtonite gabbro (perknite)
Modal name (Streckeisen / conventional)
CIPW-normative rock name
Modal rock name (cumulus)
Normative rock name (cumulus)
Description
Field name	Cummingtonite gabbro
Modal name (Streckeisen / conventional)
CIPW-normative rock name
Modal rock name (cumulus)
Normative rock name (cumulus)
Description
MAJOR ORE MINERALS
Mineral name	Description
pyrrhotite
pentlandite
chalcopyrite
MINOR ORE MINERALS
Mineral name	Description
sphalerite
pyrite
marcasite
bravoite
violarite
hematite
goethite
magnetite
OTHER MINERALS
Mineral name	Description

WHOLE ROCK COMPOSITIONS
Rock name	Location	Element or ratio	Value	Unit

MINERAL COMPOSITIONS
Mineral name	Element or ratio		Value	Unit

ISOTOPES
Description
EXPLORATION
Geochemical dispersion
Description
Geophysics
Measurement type	Response

Petrophysics
Rock name	Quantity		Result	Unit

EXPLORATION HISTORY
Organisation	Outokumpu Oy
Years	1985–1988
Operations	Gravity surveys and low altitude geophysics by GTK in 1987. Geological mapping in scale 1:1000 – 1:4000. Drilling and drill hole geopysics by Outokumpu Oy, including 3-dimensional magnetic studies and charged potential studies.
Geologists	Jorma Eeronheimo, Risto Pietilä
Drilling	Total drilling in exploration phase included 34 drill holes, altogether 7145.80 meters.
Storage
Assay data
Organisation	Outokumpu Oy
Years	1961
Operations	Bedrock mapping Geophysical surveys: magnetic, Slingram and gravity Drilling
Geologists
Drilling	6 drill holes, 424.20 meters
Storage
Assay data
Organisation	Outokumpu Oy
Years	1969
Operations	Drilling
Geologists	E. Viluksela
Drilling	48 drill holes in 10 x 10 meters grid, 1258,6 meters. In addition to this 7 drill holes (304,9 m) for geological, structural and ore geological studies.
Storage
Assay data
ORE
Ore composition	Surface ore: average grade 1,06 % Ni, 0.29 % Cu. B+C-ore: 2.06 % Ni, 0.61 % Cu, 0.1 % Co and 17.22 % S. Ni-content of the sulphide phase range from 4.2–5.6 % Ni. 86–93 % of nickel was in pentlandite, 6–14 % in pyrrhotite and in altered ore 6 % of nickel was in pyrite. Nickel content of pentalndite was 34–35 % Ni. Massive ore consisted 80 % of pyrrhotite, 10 % pentlandite and 2–5 % chalcopyrite.
Ore mineral composition	Main ore minerals are pyrrhotite, pentlandite and chalcopyrite.
Ore types	Telkkälä ore deposit consists of three ore bodies: 1) surface ore (A-ore body) including massive ore in peridotite and perknite, network and dissemination ore in cummingtonite gabbro; 2) offset ore (B ore), massive sulphide ore dyke and 3) deep ore (C ore) consists of massive, network and dissemination ore in peridotite and norite and massive ore in the contact zone of norite and peridotite
Ore sample
Primary textures
Secondary textures
Fluid
Zoning
Genetic model	Magmatic sulphides, remobilised?
Timing of mineralisation
Supergene alteration
Gangue
RESOURCES AND MINING
Extent	Surface ore (A-ore): 90 x 15–30 meters wide and 20–40 meters deep. B-ore: few meters thick, 100 meters long offset type massive sulphide ore dyke. Deep ore (C-ore): 20 x 200 meters wide, 50–80 meters high lensoidal plate dipping 25 degrees to SE.
Best sections
Ore bodies	Telkkälä ore deposit consists of three ore bodies, - surface ore (A-ore), - dyke ore (B ore) and - deep ore (C ore). A ore included 211 300 ton of ore, Ni 1.06 % and Cu 0.29 %. B ore is a massive ore dike between A and C ores C ore is about 200 meters long deposit between the levels of 110–225 m, with total ore resouces (B+C) of 335 000 ton at Ni 2.057 %, Cu 0.609 %, Co 0.098 % and S 17.22 %.
Plan figure			Longitudinal section
Economic evaluations
Resources (including production)	0.61 Mt @ 1.29 % Ni, 0.33 % Cu
Nickel content (t)	7869		Grade (Ni %)	1.29
Total production
By products	Cu
Further potential
Mining	Telkkälä deposit was mined in two phases, - first the surface ore in 1969–70, 211331 tn at 1,06 % Ni and 0,29 % Cu - the deep ore in 1988–1992, 394065 tn at 1.41 % Ni and 0.35 % Cu Total production was 605396 tn at 1,29 % Ni and 0,33 % Cu [5].
REFERENCES 1. Häkli, T.A., 1985. The Telkkälä Nickel deposit. Geological Survey of Finland. Bulletin 333, 257–263. 2. Isokangas, P. 1969. An appication for mining concession and the claim report of claim 2077. Ministry of Trade and Industry. 3. Eeronheimo, J. and Pietilä,R. 1988. Yhteenveto Taipalsaaren Telkkälän Ni-Cu-esiintymän tutkimuksista vuoden 1985 jälkeen. 4. Hänninen, E. and Sotka, P. 1988. Taipalsaaren Telkkälän Ni-Cu-esiintymän C-malmion malmimineralogiasta. 5. Isomäki O-P., 1992. Taipalsaaren Telkkälän Ni-Cu-malmiesiintymän syvämalmion geologiaa.
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