Central banks might outlaw private gold ownership and use the metal to stabilize currencies, hedge fund manager Crispin Odey said in a letter seen by Bloomberg. The notoriously bearish investor added to his gold positions throughout April, warning clients that a de-monetizing of gold could happen if governments "feel the need to create a stable unit of account for world trade." Such action isn't without precedent. The US forced private gold holders to sell their stakes in 1933 to normalize the dollar's value.