The Wayfinder of Silas Thorne

This magnificent device is a sphere of polished brass and ivory, housing a swirling core of amber light. Despite centuries in the lightless, muck-choked ruins of Aevain, the metal remains perfectly clean and warm to the touch. Layers of concentric rings etched with celestial coordinates and architectural schematics spin silently around the central core. When held by a human, the amber light pulses like a heartbeat, and ghostly, translucent blueprints of the surrounding ruins project into the air, revealing the glory of the civilization before Bablop razed it.