You have probably heard of French polish but may not know exactly what it is. French polish is probably best understood as a verb. It is a method of applying a resin (usually shellac) dissolved in alcohol with a wad of cloth and an oil to act as a lubricant. Shellac is a natural substance that is neither entirely plant nor animal in origin. An insect called the lac feeds on a host tree in parts of India and Southeast Asia and generates a hard substance to protect its egg casings from the weather. The lac resin is scraped from the twigs by hand and the result is called stick-lac. The chunks of stick-lac are broken up and washed with water to remove some coloring. When dried, it is called seedlac, which is what I use. Seedlac can be further refined into shellac by various processes.

Some may ask: Why French polish at all when modern varnishes and lacquers are more durable? French polishing, by its nature, yields a thin film which doesn't burden the instrument with undue stiffness or mass. French polishing slowly builds the finish up while varnishes and lacquers must be over-applied in order to stand up to the power buffer, which polishes the final gloss. French polish can be successfully maintained over the years and a complete refinish down to the bare wood should never be necessary. Another unique property of shellac and seedlac is the tenacious bond it forms with wood. This no doubt goes back to its original purpose of adhering to twigs in the hot tropical sun! The film is both very hard and very flexible at the same time. If a French polished guitar is dented, the finish stays with the dent and doesn't chip away. If a guitar finished with catalyzed urethane (the hardest synthetic finish) is dented in the same way, a chip is usually the result, caused by the lack of flexibility and poor adhesion to the wood. How two seemingly opposite properties, hardness (i.e. brittleness) and flexibility can co-exist in the French polished film is still a mystery to me.