Black Agate and Howlite natural stone bracelet. I Created this bracelet with 8 mm beads. Black agate is a stone which can help to bring uplifting energy which will elevate your motivation. It may help to strengthen your positive energy as well as protect your aura from negative intrusions. Howlite can help aid you in getting a restful sleep. It can also assist you in calming an overactive mind and relieve stress.