The size and type of crystal used in psychic readings does not affect the accuracy of the reading. Crystals are often used as a tool to help focus energy, but they do not have any special power that can influence the accuracy of a reading. The skill and experience of the reader is what determines how accurate their readings will be. Psychic readers use their intuition, knowledge, and spiritual connection to interpret messages from beyond for their clients. Therefore, it is ultimately up to the reader's abilities that determine how accurate a reading will be - regardless of what type or size crystal is being used.