Identifying the type of wood finish is crucial for touch-up repairs, and it can be done through a sequence of tests starting with oil, shellac, and lacquer.
What's the difference between lacquer, varnish, polyurethane, and shellac? - A Home Crafter
Four Common Finishing Mistakes (and how to avoid them)
Wood Furniture Care- How to Identify the Existing Finish
Lacquer vs. Polyurethane vs. Varnish: The Difference Between Finishes
Wood Furniture Care- How to Identify the Existing Finish
Wood Finish Identification & Finish Repair (oil, shellac, lacquer, and poly/ varnish)
Repairing Scratched Clear Coats
Comparing Laminate, Veneer, Acrylic & Lacquered Glass
Why End Coating Logs is Crucial in the Lumber Industry — Eightify
Wood Finish Shelf Life: Can Stains and Finishes Go Bad? - A Butterfly House