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I'm not really a big fan of gold as an investment. I believe it's always better to invest majority of your money when speaking of a long term time span rather than save. Stocks would be the best long term investment. Bitcoin does not have a 200 year history like the other investments shown above. so I would say it's very speculative. Bitcoin as an investment in the long term will either be an utter failure or big home run. Personally I'm betting on the latter!