chalcedony

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Queen Elizabeth II addresses at opening of Parliament. (Date unknown on photo, but may be 1958, the first time the opening of Parliament was filmed.)

All 119 References in “We Didn’t Start the Fire,” Explained

earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

The 6 Deadliest Earthquakes Since 1950

The Colosseum, Rome, Italy. Giant amphitheatre built in Rome under the Flavian emperors. (ancient architecture; architectural ruins)

New Seven Wonders of the World

The Lost Colony of Roanoke, North Carolina, where 115 people mysteriously disappeared c. 1590. John White discovers the word Croatoan carved onto a tree upon his return to the deserted Roanoke Colony in 1590

The Lost Colony of Roanoke

World Data Locator Map: Australia

Is Australia an Island?

pyramid sunset, egypt

What’s Inside the Great Pyramid?

Calendar marking march 15th

22 Questions About Time and Timekeeping Answered

chalcedony: Facts & Related Content

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Also Known As	calcedony

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agate onyx sard and sardonyx carnelian chrysoprase bloodstone plasma prase sardonyx moss agate opal garnet jade topaz turquoise jasper jadeite zircon amethyst kyanite

Quiz

Basalt sample returned by Apollo 15, from near a long sinous lunar valley called Hadley Rille. Measured at 3.3 years old.

(Bed) Rocks and (Flint) Stones