Acasta Gneiss Canada [77382] 143 grams

Why is Acasta Gneiss so important? It gives us a rare opportunity to learn so many things about Deep Time. To hold in our hands something from just about half a billion years younger than the age of the Earth and almost one-third of the age of the universe is tremendously powerful. Geologic time reference rocks like this one help us better conceptualize the division in Earth's earliest geologic history, the Hadean and Archean eons.

Acasta gneiss is the oldest relic of bedrock terrain on our planet. It has survived Earth's earliest history, giving us a snapshot into "Deep Time." We don't often have an opportunity in geology to compare the age of the Earth to the age of the Universe. Acasta gneiss is about 4 billion years old, and the universe's age is estimated to be about 13.8 billion years old. The age of the Earth is about 4.5 billion, and we are...but a smidgeon in time. But we do have an opportunity to gain a toe-hold on what geologic time means.

Acasta Gneiss is located in the remote Slave Lake province, Northwest Territories, Canada. This province is one of the oldest known zircon-bearing evolved crustal outcrops on Earth, forming during the earliest time of our planet's history, the Hadean eon. The name is taken from the nearest location, the Acasta River, east of Great Slave Lake - some good distance north of Yellowknife. The rock exposed at this outcrop formed about 3.9 to 4.03 Ga. It is an age based on the radiometric dating of zircon crystals. The Earth's surface was incredibly unstable during the earliest part of the Hadean eon. Deep convection currents in the Earth's mantle brought fiery, molten rocks to the surface and caused cooling rocks to descend into the magmatic seas. 

Few rocks and minerals remain from the Hadean eon because nearly all of this original crust has been subducted due to tectonic plate movements or other geological processes. The oldest rocks known on Earth so far are the faux amphibolite volcanic deposits of the Nuvvuagittuq greenstone belt in Quebec, Canada, estimated by some recommendations to be about 4.28 billion years old. The Jack Hills zircon rocks in Australia contain the oldest mineral grains so far found on Earth. They provide compelling evidence that has led scientists to believe that the atmosphere and oceans most likely formed before 4.4 billion years ago.

Specimen size: 60mm L X 42mm W X 27mm D; Weight: 143 grams.

Ships with a Certificate of Authenticity, tag, tag stand, and information about Acasta gneiss. Display stand and photo cube not included.

This Acasta gneiss was obtained in a materials trade with a scientific institution.

This specimen is a large, very budget-friendly and would make an important contribution to a scientific collection.

 

This scientific material is Guaranteed Authentic. It was professionally and legally collected and arrives with a Certificate of Authenticity.