Approximately 2 inches. 
Moss agate is said to encourage tranquility and emotional balance. Moss agate is the perfect stone for those who experience strong aggression or overly nurturing emotions, helping to balance male and female energies whenever they become too extreme. The calming vibe of moss agate helps bring us closer to nature as well, and can bring a sense of focus or patience when we need to disconnect from the chaos of modern society.