On the seventeenth morning, the magma rose against the bronze gates and shook the chamber. White bubbles broke on its surface. Pei Jing stood back from the pit with the Astral Bone Blade held in seven-foot tongs.
The blade had its shape. The bond between the star iron and the dragon bone still had to survive the force he meant to put through it. He looked over the five thin seams along the spine. If he let the forge get too hot, all the work he had done to seal those channels would be lost.
He held the blade over a side opening in the chimney. It took three hours for the low heat to bring the whole length to an even red. Then he set it down on the anvil and opened the pot of Shed Saint Marrow paste. The mixture of his own shed bone crystals, demon marrow fat, and star iron was the color of blood seen through a thin coat of silver.
He saved a little paste for the grip and spread the rest over the blade. The fat hissed and sent up a cloud of white smoke that smelled of burned ginseng. He waited for it to clear. A faint red sheen remained on the steel. The crystals had held the work of his mortal training. They held in the heat and sank slowly into the iron.
