Metaphysically, Black Obsidian is known for it's protective but emotionally supportive properties. 

The following are the four Reiki symbols on pyramid :

• Cho Ku Rei (Strength + Power)

• Sei He Ki (Emotional + mental healing)

• Hon Sha Ze Sho Nen (Peace + Serenity)

• Dai Kyo Myo (Reiki Master Symbol)