From Halopedia, the Halo wiki
Volatile liquid churns and boils beneath the uncertain amber surface.
Scorched cracks and violent crystal protrusions scar and pock this rocky amber terrain, torn by eruptions from the explosive molten fluid energy that bubbles and smolders beneath the surface. Pressure forces up huge bursts of the liquid, quickly solidifying into huge crystals and trapping invaluable volatile raw power inside. Nearby, an elegant Forerunner structure stretches out over the precipice overlooking endless desert dunes, housing a lift that drops deep to the solemn Archive below.