Gold to Silver Price Ratio- A trivia

I was reading an article where in it was mentioned that 'gold/silver price ratio' is going to touch 60. I got little curious, as i had heard this term for the first time.

Tried to google on this but unfortunately not too much was found. Sharing my search with you.

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When the first coins were made over 2,500 years ago in ancient Greece, the ratio of gold to silver was generally between 10:1 and 13.5:1, depending on the relative proximity of gold or silver mines. In the 1930's and 1940's the ratio reached 90:1 or higher, and in 1991 it peaked at about 98:1, although we have seen one source which claims over 100:1 peak.