From the Introduction:
This octagonal room is filled with stolen treasures. The stolen treasure, mostly coins it seem, forms large piles on the ground, making it difficult to move around. Only narrow corridors between the piles of coins remain unobstructed, like the corridor separated from the main room by the numerous columns bearing the weight of the ceiling.
Like the other rooms in this dungeon, the walls are built from solid granite blocks, set so finely that hardly even a sheet of paper would fit between them. Again numerous columns built from the same stone help distribute the enormous weight of the rock above. Besides the lanterns hung on the columns a hole where the ground has broken away to reveal molten rock flowing along below spread some light in the room, making the treasure piles sparkle.