Chalcedony has a strong influence on communication. Both on the ability to listen and on eloquence, the ability to express yourself well, diplomacy and language skills. The stone also makes people social, optimistic, cheerful, creative, open, enthusiastic and promotes togetherness in groups. Chalcedony gives self-insight, self-confidence and promotes the ability to break through resistance and accept changes. It has a positive effect on the memory and calms at moments of stress and is therefore a good stone to wear during exams. Physically, chalcedony has a cleansing, cooling and fever-reducing effect, anti-inflammatory, lowering blood pressure and promotes the immune system. The stone has a positive influence on the lungs, colds, breathing, the lymphatic system, blood and circulation, fluid accumulation and on insulin production and therefore diabetes. It strengthens the mother's feeling and stimulates milk production during breastfeeding.