What: Shares of Mechel OAO (NYSE:MTL) fell as much as 17% today as investors sold off Russian stocks because of a potential conflict with Ukraine.

So what: The Russian ruble hit an all-time low today as Moscow postured for control of Crimea, an area of Ukraine. Stock markets also fell in Russia and around the world. It doesn't help that Russia's central bank raised interest rates 1.5% today, too.

Mechel's position in Russia and $9.4 billion in debt as of December is concerning. Investors don't like the uncertainty that comes with this stock today.  

Now what: There are a lot of unknowns right now when it comes to Russia and Ukraine, but investors aren't taking the risk of owning a highly leveraged Russian company such as Mechel today. The sell-off isn't surprising but it also doesn't necessarily mean doom for the mining and metals company if the conflict doesn't escalate. That said, there are a lot of risks, and the high debt load and rising interest rates are a threat to Mechel's long-term survival. There may be a pump if the conflict cools down, but that's not a risk I'm taking today.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.