With riskier assets taking a beating last month, safe havens benefited, including gold. The SPDR Gold Shares GLD, the world's largest gold-backed exchange traded fund, jumped 2.43 percent in May while equity benchmarks stumbled.

What Happened

Gold's May rebound, which took the yellow metal above the $1,300 per ounce level, lifted gold miners stocks and the related ETFs. After gaining nearly 4 percent last Friday, the NYSE Arca Gold Miners Index (GDMNTR) finished May up 5.21 percent.

Leveraged gold miners ETFs joined the party. The Direxion Daily Gold Miners Index Bull 3X Shares NUGT, which is designed to deliver triple the daily returns of the NYSE Arca Gold Miners Index, soared more than 17 percent last week, including a gain of 12.15 percent last Friday on volume that was nearly double the daily average.

Why It's Important

The small-cap Direxion Daily Junior Gold Miners Index Bull 3X Shares JNUG got in on the act as well. JNUG jumped 15.80 percent last week with most of those gains coming by way of an 11 percent pop on Friday. JNUG looks to deliver triple the daily returns of the MVIS Global Junior Gold Miners Index (MVGDXJTR).

With gold having cleared the psychologically important $1,300 level and June historically tough on stocks, NUGT and JNUG have the potential to deliver more near-term upside.

“Gold climbed to a seven-week high on Friday, and was headed for its first monthly gain in four weeks, as investors scurried into the safe-haven bullion following Washington’s shock threat of tariffs on Mexico, which heightened fears of a global downturn,” reports CNBC.

What's Next

If this gold rally proves credible, what could be next for NUGT and JNUG could be more inflows. Data suggest some traders are already moving into the leveraged gold miners ETFs. For the five days ending May 30, traders allocated $11.86 million to the small-cap JNUG, good for the third-biggest total among Direxion ETFs during those five days, according to issuer data.

For the 10 days ending May 30, JNUG and NUGT added about $31 million combined in new assets, putting both ETFs among the top Direxion funds for inflows during that time frame.