Nuvvuagittuq Garnet Paragneiss Faux Amphibolite 1,774 gm

Nuvvuagittuq Garnet Paragneiss: Earth's Oldest Hadean Crust

This museum-grade, extra large, and extraordinary Nuvvuagittuq garnet paragneiss specimen is among the oldest rocks found on Earth. It is from the Nuvvuagittuq Supracrustal Belt, home of the rare and fascinating "faux amphibolite." Nestled along the eastern shore of Hudson Bay in Northern Canada, this geological area was formerly known as "Porpoise Cove." This specimen contains abundant garnet paragneiss.

Rare Composition

The Nuvvuagittuq greenstone belt, with a dominant lithology formed at ~4.28 Ga, would make it the only known remnant of the Hadean crust preserved on Earth. The dominant lithology of the belt has a mafic composition that consists of gneisses ranging from cummingtonite amphibolite to garnet+biotite schist composed of variable proportions of cummingtonite, biotite, quartz, plagioclase, garnet, anthophyllite, cordierite. The composition ranges from basalt to andesite and is divided into two distinct geochemical groups that are stratigraphically separated by a banded iron formation.

What does "faux amphibolite" mean?

Researchers coined the term “faux amphibolite” due to the rocks’ unique composition, which is predominantly cummingtonite, an uncommon type of amphibolite.

Age Dating

There is ongoing debate regarding the age of the NGB, with uranium-lead dating initially suggesting an age of around 3.75 billion years, while later samarium-neodymium dating indicated an age of up to 4.32 billion years. This discrepancy underscores the challenges of dating ancient rocks.

Early Life Debate

There is conjecture among scientists that there might be evidence of fossilized microorganisms in these early rocks. These supracrustal areas constitute the only areas of opportunity scientists have for the earliest biological evidence for early life on Earth. The search continues for a resolution to these questions and answers.

Key Differences in Geologic Processes of the NGB

There are key differences between the uses for the geological terms greenstone belt, banded iron formation, and supracrustal in relation to the Nuvvuagittuq locality and the rocks associated with the region.

The NGB belt consists of a diverse range of rock types, including cummingtonite amphibolite, garnet-biotite schist, and banded iron formations (BIF), with compositions varying from basaltic to andesitic. The mafic unit can be categorized into two distinct geochemical groups, separated by a BIF. The lower part is predominantly basaltic with low aluminum and high titanium content. The upper part exhibits higher aluminum and lower titanium content, encompassing a spectrum from basaltic to andesitic compositions. It is definitely an area that has experienced intense geologic processes!

Specimen Size

Size: 167mm L x 103mm W x 76mm D
Weight: 1,774.2 grams.
What's Included: Certificate of Authenticity, information, tag, tag stand, and 'in situ' regional photo. XRF included.

Why Choose This Specimen?

This Nuvvuagittuq garnet paragneiss specimen is an exceedingly rare find that would make an important contribution to any serious geological collection. Its ancient origins, unique composition, and scientific value make it a showpiece for enthusiasts and collectors alike.

This scientific material is Guaranteed Authentic. It was professionally and legally collected and arrives with a Certificate of Authenticity, information, tag, tag stand, and XRF.