Utilize the input text as a context reference, choose the right relationship between Glencore and mining from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

The FTSE 100 index drew support from gains in mining companies as the price of copper (CMCU3) rebounded, although an 8 percent drop in Glencore (GLEN.L) shares demonstrated continued volatility.

Answer: industry