Three materials stocks were recently upgraded, becoming "too cheap to ignore," but many investors might have not noticed because of the coronoavirus-related stock-market chaos, according to the analysts who cover the shares.

Morgan Stanley analyst Carlos De Alba upgraded shares of Brazilian iron ore miner Vale (VALE) to the equivalent of “buy,” according to Barron’s. Before Tuesday De Alba has suspended his rating on the stock as he weighed the potential liabilities from a 2019 dam collapse.

Bank of America analyst Timna Tanners upgraded shares of two construction-aggregate producers— Vulcan Materials (VMC) and Martin Marietta Materials (MLM)—to the equivalent of “buy” from “hold,” Barron’s said. She left her price targets unchanged on both stocks at $150 and $280, respectively. Both targets are about 17% above where the stocks have traded recently.

“Too cheap to ignore,” wrote De Alba in his Tuesday research report upgrading Vale shares. “We estimate Vale shares are now fully discounting all potential liabilities related to the Brumadinho dam collapse,” which killed 270 people.

The dollar and global equities rose on Wednesday as a strong showing by Joe Biden in the U.S. Democratic presidential primaries cheered the markets, though the economy-slowing coronavirus outbreak kept investors on tenterhooks.

Despite the day's rally, analysts stressed there was probably more trouble to come as the outbreak continues to worsen in countries outside China, Reuters explained.

"I don't think the market has bottomed. I think the market will probably fall another 5% to 10%," said Larry Hatheway, co-founder of research firm Jackson Hole Economics. "We're going to have to go lower because you've got a clear slowdown in activity that's probably going to last through the first half."

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