My favorite weird fact is that the Lunar Highlands are a different color than the Maria, mostly due to the presence of a mineral we call Plagioclase Feldspar, which we only discovered on the Moon in the last few decades, yet here on Earth there has been a gemstone composed of Plagioclase Feldspar for thousands of years called... did you guess?... Moonstone.
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What about ironic instead? Mars was named after the Roman god of war because of its blood-red color. Actually, it's a sort of pale red but that's beside the point. The point is, Mars is red because of the iron in its soil. It's also the iron in our hemoglobin that makes blood red. So although the ancients didn't know it at the time (from a factual standpoint), Mars is actually blood-red.