The heart of Optimist Mixable Color is shellac medium. This magical amber liquid is the perfect binder for all kinds of pigments because it's strong, flexible, UV-resistant, and waterproof. Unlike acrylic mediums, our Colorless Shellac makes gorgeous transparent glazes when used in high proportions with color. Add Colorless Shellac Medium to Optimist inks to make them lighter, more transparent and glossier. Using shellac-thinned Optimist colors, you can make complex, multi-layered paintings. Paper and pigment textures are more noticeable, and the ink moves more freely. With high proportions of medium, you'll create thin, shiny layers that look almost like stained glass. With smaller proportions, you can achieve bright, high-chroma colors. What is Shellac? Shellac is made by insects, much like beeswax or silk. It is a reddish, resinous substance that is deposited on tree branches by kerria lacca, informally known as a lac bug. These tiny insects are native to South Asia, which is why shellac-based inks are often called "India ink," even when they are made nowhere near India. Shellac is a natural thermoplastic, predating all synthetic plastics and offering a much better environmental profile—since there are no fossil fuels involved in shellac's synthesis. The cultivation process is much lower-carbon than other forms of agriculture, because lac farmers use existing trees to host their colonies. Lac is an economic reason to protect the forests, rather than cut them down to cultivate other crops. Once the farmers scrape the raw "sticklac" from the tree bark, they heat it over a fire to liquefy it, allowing them to filter out the bark and other impurities. Some shellac (like the premium material that we use) also undergoes dewaxing, in which the 10% wax content of raw shellac is removed. This leaves a nearly pure resin that can be turned into a food additive, a protective coating, an adhesive... or, a bottle of ink.
