E.C. Tubb 
Metal Eater 

It was the last planet left for men to conquer — a planet rich in priceless urillium ore, yet no man laid a finger on this wealth that was for the taking.For the planet Vendor could not be conquered. Space-men tried time and time again, but always the Voices drove them mad and destroyed them. Some intangible power kept men away from that taunting prize — until a scientist on Deneb IV perfected a blanketing device to protect his shop through the barrier. It took him twenty years to do it and every penny he possessed, but at last his voyage to Vendor began.It was the voyage of a gambler who knew that only two alternatives faced him…illimitable wealth and glory, or failure and death.But the journey to Vendor brought hazards that neither he nor his crew had foreseen, and before its conclusion a force was unwittingly released that could have swept life from the Universe — the indestructible and horrifying force of THE METAL EATER.