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12 Novels Considered the “Greatest Book Ever Written”

An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.

11 Egyptian Gods and Goddesses

Adolf Hitler (Nazi, nazism, German leader).

9 Things You Might Not Know About Adolf Hitler

Mayer Amschel Rothschild (1744-1855), founder of the house of Rothschild; lithograph by Friedrich Lieder, c. 1830.

Where Do Anti-Semitic Conspiracy Theories About the Rothschild Family Come From?

Plato (left) and Aristotle, detail from School of Athens, fresco by Raphael, 1508-11; in the Stanza della Segnatura, the Vatican. Plato points to the heavens and the realm of Forms, Aristotle to the earth and the realm of things.

Plato and Aristotle: How Do They Differ?

Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that

America’s 5 Most Notorious Cold Cases (Including One You May Have Thought Was Already Solved)

Thanksgiving Celebration Traditional Dinner Setting Food Concept

Why Is Thanksgiving in the U.S. Celebrated on a Thursday?

star ruby

synthetic gem

Learn about this topic in these articles:

Verneuil process

In Verneuil process: Synthetic corundum.
Star rubies and sapphires, first developed in 1947 in the United States, are made by adding one percent rutile (titanium oxide, TiO₂) to the starting powder, forming the boules in the usual manner, and then heat treating them at temperatures between 1,100° C and 1,500°…
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