Smalt is the eighteenth manuscript ink — cobalt glass ground in mortars, the blue Renaissance scribes used when lapis ultramarine was too dear. The pigment is born in fire and crushed to powder.
Drag across the pool to draw the rod through the glass dust. The deeper you draw, the darker the cobalt that lifts to the surface — and the lower the note that rings. Shallow strokes sing high; deep strokes rumble.