Norilsk Nickel, the world’s largest producer of metal, on Monday raised $6bn in loans in a sign of the resilience of investment-grade debt to the summer’s turbulence.

The Russian nickel and palladium producer saw its order books flooded by investors as they sought the safety of a solid investment-grade name. Norilsk is rated BBB- by Standard and Poor’s and Baa2 by Moody’s Investors Service.