Temperature-sensitive color change mood cabochons. Those here who a little older will remember these as Mood rings - they came with a little card that told you how passionate you were, based on the color when you wore it. They start inky black, and transition through caramel to ocean green to midnight blue as they get warmer with your body heat or ambient temperature, and change back when they get cooler.
The mood stone should be kept dry - water can effect the liquid crystal technology that makes them work and cause them to stay black.
No hole. Flat back.
Note - some of these may not have 100% even or total color change or appear somewhat mottled as they change color. We've weeded out any that don't change at least 50% of their surface.
13mm x 18mm x 7.5mm By the pack of 5.
