Ringwoodite Holds the Majority of Earth’s Water Underground

Blue Ringwoodite - Wiki CommonsFollowing up on theories that ringwoodite minerals deep within the Earth’s mantle may contain water, a BBC News report says researchers have provided the first direct evidence of this theory.

Diamonds, brought to the Earth’s surface in violent eruptions of deep volcanic rocks called kimberlites, provide a tantalising window into the deep Earth.

A research team led by Prof Graham Pearson of the University of Alberta, Canada, studied a diamond from a 100-million-year-old kimberlite found in Juina, Brazil, as part of a wider project.

They noticed that it contained a mineral, ringwoodite, that is only thought to form between 410km and 660km beneath the Earth’s surface, showing just how deep some diamonds originate.

While ringwoodite has previously been found in meteorites, this is the first time a terrestrial ringwoodite has been seen. But more extraordinarily, the researchers found that the mineral contains about 1% water.

According to the news report, this discovery is important because it solves a 25-tyear-old controversy about deep Earth being wet, dry, or wet in patches. The finding implies that the interior of the planet may store several times the water in the oceans, and demonstrates how hydrogen plays a critical role in the interior processes of the planet, and possibly other planets including Mars.

For more information on ringwoodite:

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Agates Exposed on Oregon Coast

Fire Agate
Credit: Wikipedia Wiki Commons
If you were along the Oregon Coast over the past couple weeks, you would find an agate collector’s dream.

According to the The News Guard: Regional News, recent storms in a series this winter have exposed rock beds along the coastline as the sand is washed away by the high waves and current. This makes agate hunting there hot right now.

Laura Joki, Lincoln City rockhound and owner of the Rock Your World Rock Shop, 3203 SE Highway 101, broke down what makes an agate an agate.

“Silica is the second most common element, and that’s what agates are made of,” Joki said. “An agate is crypto-crystalline quartz or quartz in which the crystals are too small to see with the naked eye, even with a microscope hand lens. They are interconnected. Almost woven together.”

Agates are formed in ocean seams called amydales—bubbles formed during volcanic lava flow. The available silicas form into agate and jasper from surrounding volcanic materials, Joki said.

She added that from the 1930s to the 1950s, a particular form of agate, known as a sagenite agate, was considered valuable.

The article also noted that there are fossils, chert, jasper, petrified wood, and zeolites to be found along the exposed shoreline.

Several of our members stay and travel to the coast often, so if you find some oceanside treasure, bring it to our meetings and events for identification and sharing.