Natural indicators are substances that can be found in nature, such as plants, and can be used to determine whether a substance is acidic or basic. They are a class of indicators that are present in nature and can be used to test acids and bases in the laboratory. Examples of natural indicators include red cabbage, turmeric, china rose, grape juice, curry powder, turnip skin, cherries, beets, onions, tomatoes, and blueberries. Natural indicators can give different colors when put into an acid or base, and the color change depends on the pH of the solution. For example, red cabbage juice turns red in acidic solutions and green in basic solutions. Natural indicators can be used to distinguish between acidic and basic substances, and they are often used in schools and universities to teach chemistry.