Silver ETFs are outperforming gold prices again after a four-day break. The iShares Silver Trust (NYSEArca: SLV) vaulted nearly 4% on Tuesday while SPDR Gold Shares (NYSEArca: GLD) added 0.5%.

Silver was leading gold after strong manufacturing data in the U.S. and China.

“Manufacturing is a key driver of silver demand as it is used in solar panels and electronics as well as jewelry,” reports.

There are also signs that silver ETFs have provided support for the metal’s price.

For example, since the start of the year, gold ETFs have seen their bullion holdings reduced by 680 metric tons, or a quarter of their holdings, the Financial Times reports.