EDIT Sun Symbol This symbol is used on astroligcal charts to represent the sun. The position of the sun in a certain zodiac sign in the moment of birth is believed to influence a person's whole life.
The symbol itself is very old, variations of a centered circle representing sun, light, live can be found throughout human history and cultures.

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EDIT Symbol for gold in alchemy.

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EDIT On nautical charts this ideograph is used for chimneys, towers, and all high structures in general that are visible from the sea.

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EDIT Gone home Originally, this was a sign used by American indians. The founder of the boy-scout movement, Baden Powell, taught the scouts a series of trail markings, and this was one of them. A hiker uses it so say »I reached my designation and have gone home«. After Baden Powells death in 1941, it was put on his gravestone in India and since then the boy scouts also use the term »gone home« to refer to someone who died.

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EDIT Earth In the middle ages the church believed the earth to be the center of the universe, so the scholars used this sign for the »earth surrounded by the great ocean«.

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EDIT Archangel Michael In Cabbalistic mysticism, the sign is used to represent the archangel Michael because he isregarded to be related to the sun and the day of the sun – sunday.

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