OBSIDIAN 
Composition: Volcanic Glass. 70–75% SiO2, plus MgO, Fe3O4
 
Brings comfort in times of grief. Inspires forgiveness & releases grievances. Aids growth and particularly good for children. Helps reduce food craving. Reduces the pain of arthritis and joint problems, Shields against negativity. Protective, stabilising internal & external energies. Brings purity & balance.