Utilize the input text as a context reference, choose the right relationship between 'Glencore' and 'Mining' from the options.
Options: industry, manufacturer, publisher, employer

Mining groups BHP Billiton (NYSE: BBL - news ) , Glencore (Xetra: A1JAGV - news ) , Antofagasta (Other OTC: ANFGF - news ) and Rio Tinto (LSE: RIO.L - news ) were down between 2.3 and 4.7 percent.
industry