The Stone Furnace is a basic, blocky structure with a simple geometric shape, featuring a square base and a slightly tapered top to resemble a crude chimney. Constructed from rough-hewn stone blocks, it has a textured, uneven surface with visible mortar lines between the stones. The front has a small, rectangular opening for fuel and materials, with a subtle glow emanating from within to indicate active smelting. The color palette is muted, primarily consisting of grays and browns, with slight variations to mimic natural stone. The design is functional and utilitarian, fitting the game's industrial theme.