Dumortierite Flat Smooth Stone / Slice

Dumortierite
Assists in communication with angelic or spirit guides
A stone of the mind
Strengthens mental acuity and memory, especially in areas related to math and language
Promotes confidence and a positive attitude toward life
By sharpening focus and acuity, can help strip self doubt and heighten one's ability to stand up for one's self
 
These are priced by weight and not necessarily by size.