In the cooling bay behind Furnace One, the second plate had already been uncovered from an earlier trial pour. It lay on a heavy oak check frame stand, measuring four feet wide by six feet long, its surface a dark, semi-clear bottle-green laced with cloudy ribbons of metal copper. The slab had cooled to perhaps two hundred degrees. It was still hot enough to blister bare skin through thin cloth. But stable enough to examine under focused lantern light.
The cooling bay was quiet compared to the roaring inferno of the casting floor fifty paces away. Here, between stacked tiers of cured fire-brick and rough pine shipping crates, the air was warm and smelled of cooling borax, bitter sulfur dust, and dry cedar shavings. A cold alpine draft slipped through the corrugated iron angled slats high in the northern roof edges, mixing with the sharp, stone heat streaming from the brick floor. Overhead, a single copper lantern hung on a counterweighted iron crane. He cast an amber cone of light across the massive slab of hardened glass.
Ivara Quill set her check lantern beneath the oak frame stand, adjusting the copper mirror until the beam shot straight upward through the thickness of the glass. She leaned over the slab, squinting through the dense green medium. The material was solid, heavy as quarried dark rock, and devoid of bubble clusters or surface scabs. But near the upper left corner, four inches from the rough, unground outer edge, a hair-thin line caught…
