Shellac is a natural resin secreted by the female lac bug (Kerria lacca), primarily found on trees in India and Thailand. The term “shellac” is derived from the French word laque en écailles, meaning “lac in thin plates,” referencing its flake-like form after it has been refined and dried.
The English word traces its roots through the Hindi lākh, itself related to Sanskrit lākṣā, meaning both the lac resin and the number 100,000, a nod to the massive quantity of insects needed to produce it. Shellac has been used by humans for centuries, with references to lac dyes and coatings appearing in ancient Indian texts and being brought to Europe through trade as early as the Middle Ages.
The production of shellac begins when lac insects1 colonize certain trees, especially the Ficus or Schleichera species, secreting a resinous coating on branches to protect their larvae. The encrusted twigs, known as “sticklac,” are harvested and scraped clean. This raw material is then crushed, sieved, and washed to remove insect parts and other debris. The purified lac is melted, filtered through cloth to remove remaining impurities, and stretched into thin sheets which are dried and broken into flakes.
These flakes are sold commercially and can be dissolved in alcohol to create a brushable or sprayable finish. Depending on processing, shellac is available in a range of colors from pale blond to deep garnet, determined largely by the species of tree used, the insect strain, and how much it’s been bleached or refined. Shellac has unique properties that have made it valuable across a wide variety of industries.
It forms a hard, glossy surface that enhances the appearance of wood while also offering some degree of protection. It is also non-toxic, fast-drying, and has natural adhesive properties. Unlike many synthetic finishes, it is reversible with alcohol, allowing easy repairs or touch-ups. It is, however, sensitive to heat, water, and alcohol, which limits its use in certain environments. Still, its biodegradability and safety for food and pharmaceuticals keep it relevant,
especially in an age of increasing interest in sustainable materials. Historically, shellac was widely used before the development of modern synthetic resins. It was the dominant wood finish before being supplanted by nitrocellulose lacquer2 in the 1920s and 1930s. During the phonograph era, shellac served as the primary binder for 78 RPM records,
giving them their distinctive hardness and brittleness. The advent of vinyl led to its decline in that application, but it remained in use for decades in electronics as an insulating varnish and in the food industry as a glaze or coating. Even today, shellac is listed as E9043 when used as a food additive and is found in products like candy coatings, pill capsules, and fruits to give them shine and durability.
Beyond woodworking, shellac’s versatility is astonishing. It has been used as an ink base, a fixative in cosmetics, and a binding agent in grinding wheels. Its insulating qualities made it invaluable in the early days of radio and electrical components. The film industry once used shellac as a binder in early film emulsions.
Because it is food-safe and hypoallergenic, it’s also used in nail polish and hair sprays, though synthetic alternatives have largely taken over these roles. Artists and restorers still prize shellac for its use as a sealer or primer, especially when dealing with problematic stains or odors. Trivia surrounding shellac includes its role in everyday language;
the phrase “getting shellacked” derives from the intense gloss and heavy coating the resin provides, metaphorically linked to receiving a heavy defeat. Another curious fact is that over 300,000 lac insects are needed to produce just one kilogram of shellac,
highlighting the immense labor of nature behind each flake. Although synthetic materials have replaced shellac in many industrial applications, its natural origin, ease of use, and elegant finish ensure it retains a loyal following among traditional woodworkers, luthiers, and conservationists.
Footnotes
- Lac insects, primarily Kerria lacca, are tiny scale insects native to Southeast Asia, particularly India and Thailand, that are cultivated for their resinous secretions used to make shellac, dyes, and varnishes. These insects infest specific host trees—commonly species like Schleichera oleosa and Ficus religiosa—by clustering on the branches and excreting a sticky resin that encases them for protection during development. Female lac insects are wingless and largely immobile, producing most of the resin, while the smaller, short-lived males mature to mate and then die. Lac cultivation, or “lac culture,” is a traditional agroforestry practice dating back centuries, providing a valuable non-timber forest product that supports rural economies. The life cycle of the lac insect includes egg, larva, pupa, and adult stages, and farmers carefully manage crop cycles to maximize resin yield. Beyond resin, the dye extracted from lac has been used in textiles and cosmetics for thousands of years. With renewed interest in sustainable and biodegradable materials, lac insects continue to be vital to both local economies and natural-product industries. ↩︎
- Nitrocellulose lacquer is a fast-drying, solvent-based wood and metal finish derived from cellulose treated with nitric and sulfuric acids to produce nitrocellulose, a highly flammable compound originally used in explosives. First developed in the early 20th century and popularized in the 1920s, it became a revolutionary material in the automotive and furniture industries due to its quick drying time, ease of application, and beautiful, high-gloss finish. Unlike shellac, nitrocellulose lacquer could be sprayed and built up in multiple layers, which were then sanded and buffed to a mirror-like surface. However, it remains susceptible to yellowing, crazing, and solvent damage over time. Despite the development of more durable coatings like polyurethane and polyester, nitrocellulose lacquer is still prized in vintage instrument finishing and traditional woodworking for its tonal and aesthetic qualities. Its use is restricted in some areas due to environmental and safety regulations, as it releases volatile organic compounds (VOCs) during application. ↩︎
- E904 is the food additive code for shellac, a natural resin secreted by the lac insect (Kerria lacca) and commonly used as a glazing agent to provide a shiny, protective coating on food products, pharmaceuticals, and confections. It is often found on candies, chocolate-coated products, coffee beans, fruits, and dietary supplements, where it enhances appearance and prolongs shelf life by forming a moisture-resistant barrier. Because shellac is derived from insect secretions, it is not considered vegan, though it is generally recognized as safe (GRAS) by the U.S. Food and Drug Administration and approved for use in the European Union under the E-number system. Shellac used in food is purified to remove insect parts and contaminants, and it must meet food-grade standards to be labeled as E904. Its biodegradability and non-toxicity make it a favored alternative to synthetic coatings in some applications. ↩︎
Further Reading
Sources
- Wikipedia “Shellac” https://en.wikipedia.org/wiki/Shellac
- Britannica “shellac” https://www.britannica.com/topic/shellac
- Newton Makes “Easy Shellac Finish” https://www.newtonmakes.com/blog/shellac-how-to
- Natural Pigments “Shellac—Applications and Use in Art” https://www.naturalpigments.com/artist-materials/shellac-use-art
- ScienceDirect “Shellac” https://www.sciencedirect.com/topics/medicine-and-dentistry/shellac
