The best performing metal this week was palladium, up 7.80 percent, scoring an eight-month high of $1,053.40 on Thursday, due to stockpiling by China, writes Kitco News. The World Gold Council reported this week that central banks added a net total of 193.3 tonnes of gold to their reserves in the first six months of 2018, representing an 8 percent increase from the same period in 2017 and the strongest first half of the year since 2015.