Agate is a stone of protection and strength. It protects and strengthens the mind and spirit. It's is also a useful stone for cleansing the energy and protecting against negative thoughts and emotions. It's a stone that aids in problem solving and encourages searching for a solution, rather than dwelling on the problem. It also encourages conscientiousness and vigilance in tasks and helps maintain an ever-present watchfulness during the activities requiring circumspection, deliberation, or vigilance.