Some Archean Rocks
Acasta Gneiss - 4.031 Ga granodiorite gneiss from the Acasta River, far-northern Canada.
Greenlandite - 3.8 Ga fuchsite-quartz gneiss from southwestern Greenland.
Isua Supracrustal Belt - 3.8 Ga banded iron formation from southwestern
Greenland.
Barberton Greenstone Belt - 3.482-3.657 Ga komatiite from northeastern South
Africa.
Carbonado diamondites (mid-Mesoarchean, ~3.2 Ga) - supernova rocks that
impacted on Earth in the Brazil and Central African Republic area (these were
originally next to each other, before the ancient Gondwana continent rifted
apart).
Compeau Creek Gneiss - ~2.6-3.0 Ga (?) from near Marquette, Michigan’s
Upper Peninsula, USA.
Carbon Leader Gold Ore - 2.9 Ga auriferous, uraninitic stromatolite rock
from the Blyvooruitzicht Gold Mine, South Africa.
Witwatersrand Conglomerate - 2.76-2.89 Ga auriferous, pyritic quartz-pebble
conglomerate from the Stilfontein Mine, northeastern South Africa.
Goldman Meadows Iron-Formation - 2.87 Ga magnetite BIF from the Atlantic City Iron
Mine, Wyoming, USA.
Red Lake Gold Ore - 2.85 Ga altered basalt with 2.712-2.723 gold
mineralization from the Red Lake Mine, Ontario, Canada.
Belomorian Complex - 2.7-2.8 Ga retrograde eclogite from near Polarnie
Zory, Kola Peninsula, far-northwestern Russia.
“Kinawa Granite” - 2.72-2.75 Ga migmatite from
southeastern Brazil.
Stillwater Complex - 2.71 Ga chromitite from the Beartooth Mountains of
southern Montana, USA.
Stillwater Complex - 2.71 Ga sulfidic serpentinite (left) & sulfidic
tremolitite (center) & massive PGE-rich sulfide (right) from the
Stillwater Mine, Beartooth Mountains, southern Montana, USA.
Pyke Hill Komatiite - 2.703-2.715 Ga komatiite from Pyke Hill, eastern
Ontario, Canada.
Cadillac Gold Ore - 2.7 Ga hydrothermal quartz-gold vein from the
Cadillac Mine, Quebec, Canada.
Temagami Iron-Formation - 2.7 Ga jaspilite from the Sherman Iron Mine,
Ontario, Canada.
Prohibition Iron-Formation - ~2.7 Ga ferruginous banded chert from near
Meekatharra, Western Australia.
Mona Formation - ~2.7 Ga phyllite (left) & greenstone (right) from
the Marquette area, Michigan’s Upper Peninsula, USA.
Kitchi Formation - ~2.7 Ga volcanic metabreccia at Deer Lake,
Michigan’s Upper Peninsula, USA.
Ely Greenstone - 2.6-2.7 Ga epidotite from the Dunka Mine area,
Minnesota.
Deer Lake Peridotite - ~2.5-2.7 Ga (?) serpentinite from Deer Lake,
Michigan’s Upper Peninsula, USA.
Keivy Schist - staurolite schist having a 2.5-2.7 Ga protolith age from Mt.
Ploskaya, east-central Kola Peninsula, Murmansk Region, far-northwestern
Russia.
Sar-e-Sang Lapis Lazuli Deposit - 2.7-2.4 Ga (?) lazuritic metamorphite (right)
& lazuritic-pyritic marble (left) from the Sakhi Formation (Neoarchean,
2.4-2.7? Ga) in the Sar-e-Sang Mining District, Hindu Kush Mountains,
northeastern Afghanistan.
“Nuummite” - 2.68 to 2.77 Ga anthophyllite-gedrite
amphibolite from an island south of Nuuk, southwestern Greenland.
English River Subprovince intrusion - 2.66-2.71 Ga porphyritic granite from Second Mountain Quarry, western Ontario, Canada.
Orbicular granodiorite - 2.687 Ga decorative stone from Warroan Hill,
Western Australia.
Timiskaming Conglomerate - <2.674 Ga polymict conglomerate having komatiite
& BIF pebbles from Kirkland Lake, Ontario, Canada.
Preissac-Lacorne Batholith - 2.630-2.675 Ga molybdenite-quartz pegmatite sample
(left) & bismuthinite-quartz-K-feldspar pegmatite sample (right) from Moly
Hill, Quebec, Canada.
"Dakota Mahogany Granite" - 2.6-2.7
Ga porphyritic granite from the Milbank Granite near Milbank, South Dakota,
USA.
"Tan Brown Granite" & "Sapphire
Brown Granite" - Archean porphyritic granites from Andhra Pradesh
State, southern India.
Orthogneiss from the Mesoarchean or Neoarchean along the Beartooth Highway,
southern Montana, USA.
Belomorian Terrane - Neoarchean ruby-bearing garnetiferous orthogneiss
from Khit Island, Karelia, Russia.
Great Dike of Rhodesia - 2.57-2.58 Ga chromitite (with serpentine) from the
Caesar Mine, northern Zimbabwe, southern Africa.