The Ruby Knight by David Eddings
Book two of the classic ELENIUM trilogy. The quest for the jewel of life continues. Time is running out for poisoned Queen Ehlana and if she is to be saved Sparhawk must find a powerful artefact called the Bhelliom before it's too late. But finding the rose-shaped sapphire, once mounted in the crown of the Thalasian King Sarak is no simple task. No one has set eyes upon it since his death in the heat of a legendary battle. To make things worse, Sparhawk and his allies are not the only party looking for the Bhelliom. The evil god Azash has plans for it himself, and Ghwerig the mad troll-dwarf has been ceaselessly searching for the artefact for centuries, intending to retrieve it at any cost.