A single wood‑cased pencil whose core is specially formulated (wax‑based) to mark on smooth surfaces like glass, metal, vinyl and more. The mark is designed to be bold/visible even on non‑paper surfaces. The pencil may come in a specific colour version (for example white for marking on dark glass, black/blue for lighter surfaces). It is sharpenable like a standard pencil, and the lead is formulated so it doesn’t scratch the surface but still leaves a visible trace.