Gold is found in many forms on earth. It is found in alloys with silver and mercury, in combination with other ores, or as gold nuggets in pure form. The latter is 85 to 95 percent pure gold. Alaska has been a favorite destination for gold diggers for over 100 years. Especially the place called Ruby. The largest gold nugget, the centennial gold nugget, found in Alaska weighed 9 kilograms.