What happened

Shares of gold miners Eldorado Gold (NYSE:EGO)Gold Fields (NYSE:GFI), and Hecla Mining (NYSE:HL) all closed with 10% or better gains on Feb. 18. Today's move upward is a long-awaited positive for many investors, who have seen all three fall by double digits so far in 2020. Even after today's gains, Eldorado Gold and Hecla Mining shares are still down 9% and 4% year to date. 

So what

Today's jump was largely a speculative move upward on investor interest in gold. Gold prices have steadily edged higher since late in 2019, in part because of increasing concerns over the global implications of COVID-19, the strain of coronavirus that's already killed more than 1,300 people and bringing parts of China's economy to a standstill. The International Energy Agency recently revised its forecast for global oil demand for the first quarter of the year and now expects the impact of coronavirus on that country's economic output to lead to the first quarterly drop in oil demand in over a decade. 

Gold egg in a carton of regular eggs.

Are these miners a golden goose, or will they lay an egg? Image source: Getty Images.

What does that have to do with gold? Directly, not much -- though ironically it could actually reduce industrial demand from manufacturers. But if there's one thing investors hate, it's uncertainty. However, economic uncertainty is often a boon for gold prices, and that's great for gold miners like these. Here's what gold prices have done over the past few months: 

Gold Price in US Dollars Chart

Gold Price in US Dollars data by YCharts

Gold prices are now at the highest levels in about six and a half years, and above $1,600 per ounce for the first time since 2013. 

Now what

COVID-19 coronavirus is likely to remain a source of uncertainty for months to come, with victims both human and economic. However, it's almost certain to prove a speed bump, little more than a historical footnote, and not a global pandemic that brings the world economy to a screeching halt. (Can you name anyone who made a fortune during the SARS outbreak? Me, neither.) 

And just as quickly as investor interest -- or speculation, more accurately -- has helped drive gold prices higher, the next shiny object will come along and could send gold prices falling. The catch here is that even a modest drop in gold prices would probably result in a dramatic drop in the stock prices of these three precious-metals miners, as investors look to move quickly to get out the door. 

Add it all up, and here's what every investor considering gold needs to know: There may be some quick money to be made in gold miner speculation if gold prices do continue climbing. But there will also be plenty of losses on the other side when the rally comes to an end. Far too many investors will end up there.

Before you make a bet on any gold stock, learn how to invest in gold stocks so you can avoid big mistakes.