MP Materials is trading at $39.89, down 4.13%, amid broader selling in rare-earth and critical-minerals stocks. - Reporting describes sector-wide selling, with no fresh company-specific catalyst. - The wider market is weaker: the S&P 500 is down 1.36% and Nasdaq is down 2.40%, adding to risk-off pressure. No verified news today directly explains the move; the sector decline is the clearest context.