Each crystal has its own personality, so we can't easily assign someone to a single sign. The following list is, therefore, purely indicative and is only given to those who absolutely want a zodiac amulet. Certainly some stones will appeal to you more than others and suit your character better, but even an opposite element crystal can be useful. For example a very nervous Gemini could use a peridot to calm them down, even though it is supposed to be primarily a Fire and Leo gemstone.