What happened

Century Aluminum Company (CENX -2.76%) shares are leading metal stocks higher with a 10.9% advance as of 2:13 p.m. ET, followed closely by similar gains from Alcoa (AA -3.13%), Southern Copper (SCCO -1.43%), and Rio Tinto Group (RIO -0.06%). While metal pricing has been tepid of late, headlines suggest it might be on the verge of improvement.

That's far from being a guarantee, however. 

So what

Thank Alcoa, mostly. The aluminum company is publicly calling for government sanctions on metals exported from Russia, as well as bans on metals sold to Russian buyers. Separately but simultaneously, Alcoa is requesting the London Metal Exchange delist any Russian metals from its trading platform. The company argues the mere presence of Russian metals in the global marketplace not only damages the credibility of the exchange, but poses the risk of future price disruption.

Neither the London Metal Exchange nor any additional governments have indicated they're taking these suggested actions, which would certainly -- even if only temporarily -- buoy metal prices. The market's response clearly indicates such action is a distinct possibility, though. In addition to names like Alcoa and Century Aluminum jumping, aluminum prices are up on the order of 4% Friday.

It's not just aluminum, either. Copper prices are soaring today too, up 7% on rumors that China could soon be easing its COVID-19 restrictions and subsequently reigniting economic growth. That prospective increase in demand would materialize at the same time copper supplies are set to shrink. Chinese miner MMG's Las Bambas copper mine in Peru announced on Thursday it will be scaling back operations at the site. Protests from local and nearby inhabitants continue to disrupt output, threatening an already-thin global supply of the soft metal.

Of course, continued inflation also supports higher commodity prices. The Federal Reserve raised the fed funds rate another 75 basis points earlier this week in its ongoing effort to curb inflation. Language from Fed Chairman Jerome Powell, however, implies the central bank fears that continued consumer and producer price increases are likely.

Now what

Today's gains from companies like Southern Copper and Rio Tinto are encouraging to metal stock investors who had watched copper and aluminum prices fall since March. But, know that these sorts of underpinnings can fade as quickly as they develop.

Consider this: The London Metal Exchange may opt to do nothing to bar Russia-supplied copper and aluminum from being bought and sold via its platform. It's been mulling the possibility since early last month, after all, and thus far has made no official commitment to the idea. Meanwhile, although MMG's decision to curb activities at its Las Bambas copper mine is head-turning, that mine itself only makes up a modest 2% of the world's copper supply.

Other sources can offset its decreased output, like HudBay's newest project. The miner recently unveiled its initial resource estimate for its Llaguen copper mine in the Otuzco province in Peru, indicating 271 million tonnes of 0.33% copper and 83 million tonnes of 0.24% copper in addition to many other marketable metals.

Investors looking for growth from the industrial metals sliver of the basic materials sector will want to wait for evidence of more sustainable price support -- like actual economic growth -- before stepping into these stocks for the long term.