A Thunder Egg is a nodule-like rock, similar to a filled geode, that formed within volcanic ash layers. They are usually composed of quartz, agate, opal, and/or visibly crystalline quartz-like Agate. It is a grounding, soothing and calming stone that creates emotional and intellectual balance. This stone will aid in cantering and stabilizing energy. It also promotes self-acceptance and confidence, encouraging the speaking of one’s own truth.