Rocks on Earth originally formed through impact melting as well as the cooling of a magma ocean.
As the young planet Earth accreted cosmic dust and planetesimals 4.5 billion years ago, the immense heat as well as the asteroid impacts caused the outer layers to melt and as the molten rock cooled down, the very first primitive, volcanic crust then solidified.
The formation of the first rocks on Earth formed in several stages which includes.
Magma Oceans, where repeated collisions as well as the decay of radioactive elements kept early Earth in a molten state.
And as the surface lost heat to the cold vacuum of space, a thin and unstable crust began to crystallize.
And this early crust was also likely composed of ultramafic volcanic rock that is similar to komatiite, which was rich in the mineral olivine, and primitive basalt.
And these first solid rocks went through continuous recycling, where they were constantly fractured, melted, and destroyed by continuous asteroid bombardments and intense tectonic activity during the Hadean Eon.
And as a result of the constant recycling, no pristine and unbroken rocks survive from the earliest days of the Earth.
The oldest surviving in place rock formations, like the Acasta Gneiss in Canada, date back as far as 4.03 billion years.
And meanwhile, the oldest known remnants of Earth's materials are microscopic Zircon Crystals in Western Australia, which date back to roughly 4.4 billion years.
The oldest rock in the USA is Watersmeet Gneiss, which is located in the Upper Peninsula of Michigan near the town of Watersmeet.
Zircon crystals have been dated by researched to be around 3.6 billion years old, with some grains being as old as 3.8 billion years old.
Although the Watersmeet Gneiss holds the crown for being the oldest intact rock unit in the country, the United States, has several other locations, which also have incredibly ancient continental crust, which include.
Michigan's Watersmeet Gneiss: Discovered to be America's oldest, this rock is located in northern Michigan and is part of an ancient east-west geological belt crossing the upper midcontinent.
Minnesota River Valley: Known as the Morton Gneiss (or "rainbow gneiss") and Montevideo Gneiss, these ancient rocks are roughly 3.5 to 3.6 billion years old and are some of the oldest exposed rocks in the contiguous U.S..
You can see these rocks outcropping in southwestern Minnesota at the Morton Outcrops Scientific and Natural Area.
Wyoming: The Wyoming Province features rocks and zircon grains that also trace back roughly 3.5 to 3.8 billion years old.
The very first rock that formed on Earth looked like and were dark, crystalline and ultramafic lavas that are called komatiites.
Because the young planet Earth was extremely hot when these rocks formed, the mantle of Earth generated highly magnesium rich magmas, which also pooled and also solidified as dark and heavy crust that looked much different than the granites that we see today.
Also before the surface of Earth solidified, the planet earth was a churning magma ocean.
The absolute oldest surviving remnants of Earth's rock record, which dates back over 4 billion years and are hard, banded rocks that are known as gneiss, like Acasta Gneiss in Canada, or basaltic crust that is found in the Nuvvuagittuq Greenstone Belt.
These rocks were also largely composed of a mineral called olivine and dark pyroxenes, which give them a dark, greenish-black, and sometimes speckled or layered appearance and if you look before Earth formed, the first rocks in our solar system were also cosmic dust and ice aggregates, which collected to form asteroids and the earliest planetary cores.
Zircon is the oldest known gemstone on Earth and is also known as the oldest material on Earth other than the Komatiites.
Zircon crystals have been discovered in the Jack Hills of Western Australia and have been dated to be as old as 4.4 billion years old.
The Zircon crystals or gemstones formed just 160 million years after the planet Earth itself had formed and survived as tiny and resilient time capsules.
The Zircon crystal and gemstone is extremely durable and can easily survive extreme heat, pressure and even the erosion of the rocks, in which it had originally formed from.
Natural zircon crystals and gemstones are available in a brilliant palette of colors, which includes red, yellow, brown, green and even highly prized blue varieties.
Colorless zircon crystals and gemstones are also known for their intense "fire" as well as brilliance, and have been used for centuries as a stunning natural alternative to diamonds.
Zircon is also officially recognized as being one of the birthstones for the month of December.
Zircon is a naturally occurring zirconium silicate mineral (ZrSiOâ‚„) that is also renowned in geology for its durability and radioactive dating capabilities, and in jewelry for its intense brilliance.
Zircon also often contains trace elements like uranium, making it an invaluable tool for scientists studying Earth's ancient history.
And because zircon incorporates uranium during their formation, which decays into lead at a known rate, the zircon crystals allow geologists to accurately calculate the age of the rocks that they reside in.
Zircon crystals measure 6 to 7.5 on the Mohs scale, which makes it relatively soft for daily rings when compared to diamonds or sapphires, although zircon crystals are still ideal for earrings and necklaces.
Natural and untreated blue or vibrant red zircon crystals can range from $150.00 to several thousand dollars in price, depending on the carat weight as well as the cut and clarity.
And zircon is also a 100 percent natural mineral, whereas Cubic Zirconia is a man made synthetic (zirconium dioxide), which is often used as a diamond simulant.
Zircon can also sometimes lose it's color or even fade if it's exposed to any harsh and bright sunlight for extended periods of time.
Rocks are made of multiple minerals and there are also other oldest intact rock formations on Earth, which include:
The Nuvvuagittuq Greenstone Belt (Quebec, Canada): Recent studies date sections of this ancient ocean floor to about 4.16 billion years ago.
The Acasta Gneiss Complex (Northwest Territories, Canada): These are the most universally confirmed and widely agreed-upon intact rock formations, dating back 4.03 billion years.