The blue dust that covered the floor flags of Entry hall 536 was not cold ash.
It was the crushed residue of Master Astronomer Chen’s heart-core, dropped from the seams of Zhu Heling’s sample crates as the hired blades hauled their loot toward the north. In the pale green draft from the air-flow chimney pipes, the sapphire specks sparkled with a faint, persistent eerie glow. A tiny, dying star-pattern scattered across forty paces of soot-blackened pale limestone.
Qiao Ming stopped at the threshold of the chamber.
He knelt upon both knees, setting his Folded brass star-compass upon the flat surface of a fallen marble top door beam. His hands, rough and permanently stained with blue-black silt-ink, were steady. He reached into his breast pocket and drew out the green rust bone-awl.
The eight-inch tool caught the blue light on its polished whalebone shaft. The three-sided bronze tip, sharpened on fine emery stone five hundred years ago, was clean, clean, flawless by any trace of oil or rust.
Yan Zhiqiu knelt beside him, the Broken Slate resting across her thighs. She watched in silence as the land-mapper lowered the point of the awl to the floor.
Qiao Ming pressed the bronze tip into a small buildup of the glowing blue dust.
