Black Obsidian Tumbles #2 measure approximately 3/8" to 3/4". Please let me pick one for you. These are $.50 USD each.
(Healing Crystal, Grounding and Protecting Crystal)
Obsidian is more or less volcanic glass that comes in a range of colors. Most Obsidian is black and is very grounding and protecting. Obsidian is more connected to Mother Earth than other grounding crystals; the connection is quite strong. It shields you against negativity. It is useful to help healers see the cause of dis-ease.