Highlighter dust is used to give a high sheen finish to gumpaste flowers or fondant. Either dry brush on or mix with an alcohol-based product such as pure lemon extract and paint on for stronger color results. 2 grams. The highlighters are for decorative use only, and shouldn't be eaten. The color chart above is designed to give you some idea of the color, depending on your internet connection and the quality of your monitor, the true colors may vary slightly from the chart.