Traders said investors were being forced to cover losses from stocks.

With the declines in stocks and commodities accelerating, investors have favored safer assets, including gold and bonds that tend to hold their value during times of market turmoil. That trend pushed gold to its highest level in seven years last week and sent the ratio of gold prices to oil prices to its highest point since early 2016. During that selloff four years ago, fears that an economic slowdown in China would spark a recession pushed crude prices below $30 a barrel.
But the recent market chaos even engulfed gold late last week, sending prices down 4.6% Friday. Traders said investors were being forced to cover losses from stocks. Another explanation: margin calls from banks to investors who had used some of their stock portfolios as collateral to buy other securities. With the value of those positions shrinking substantially, banks can demand repayment.

Full article: https://www.wsj.com/articles/deepening-rout-in-commodities-stokes-fears-about-world-economy-11583064001