The dragon's head (also called Anabibazon in astronomy and astrology) and dragon's tail (also called Catabibazon) were in use from ancient times. In heraldry the dragon's head symbolizes a light colour (tenné), and dragon's tail symbolizes a dark colour (sanguine). In alchemy the dragon's head is the materia prima that is subjected to transmutation to produce the philosopher's stone. During the process of transmutation the light-colored starting material is transformed to a darker and more reddish one. In astrology the dragon's head is connected to good luck, while the dragon's tail is unlucky. These links indicate that heraldry in the 15th century was strongly under the influence of magical views and alchemistic ideas, which were in turn connected to the lore of sympathies between colors, planets, gemstones, metals, virtues etc.