Blue Kyanite comes from the Greek word kyanos meaning deep blue (it is less often found in black, green, or orange). It has been used for centuries to help improve one's ability in speaking the truth, communicate clearly, and being honest with themselves as well as others around them- especially when it concerns meditation or intuitive abilities because this mineral helps detect sincerity/truthfulness.
A rough version of crystal is usually cut from a much larger piece of mined material that is too large or heavy to be used by a person. Rough chunks such as calcites are often acid-washed to subtly smooth out rough edges that may cause cuts or injury and to prevent further flaking or breakage.