MINING: 300 workers laid off as 100-year-old molybdenum mine closes Published: Tuesday, June 3, 2014 A 100-year-old molybdenum mine in New Mexico is shutting down, resulting in the layoff of 300 workers. Please subscribe to Greenwire to read the full story. Username: Password: Forgot your access codes? Recover them. Not a subscriber? Sign up for a trial. Ready to subscribe? Click here.