These are tumbled pieces of Snowflake Obsidian. 
 
Metaphysical Correspondences:
 
Chakras: Throat, Heart, Root
Issues, Intentions, & Powers: awareness, concentration/focus, energy(spiritual),
negativity, protection(from spiritual drain), purification, wisdom
 
Please note that these are natural stone and therefore may have inclusions. Each piece is unique and may not reflect identically what is shown in the display photo.