Final answer:
The decoration on the Inkstone box (Suzuribako) from the late 18th century is lacquered wood.
Step-by-step explanation:
The decoration on the Inkstone box (Suzuribako) from the late 18th century is lacquered wood. Lacquer is a traditional Japanese technique used to decorate and protect wooden surfaces. The wood is coated with multiple layers of lacquer and then polished to create a smooth and glossy finish. This technique allows for intricate designs and motifs to be applied to the surface of the box, making it a highly desirable decorative art form.