She poisoned him with gold sodium thiomalate. She was sprinkling it on his cornflakes. It had been his favorite food since they met in the ninth grade. He ate them every morning, and every morning for the last week she sprinkled his cornflakes with gold sodium thiomalate. In the end the gold poisoning made his skin burn, and his throat close up. They treated him for all sorts of things, but in the end she killed him with gold. It's kind of poetic, actually.