The photos demonstrate a sampling of the various colors you can achieve in each bead. These mirage mood beads change color as their temperature changes! Your body temperature as well as the ambient temperature will affect the color that is brought out.
These are made from polymer clay and have a thermo-sensitive liquid crystal layer on top. It's that liquid layer that provides the change in color. As a bonus, these beads have larger holes that accommodate up to a 3mm cord of your choice.
Whether mood jewelry actually works or not remains to be seen, but here is a list from the web that explains the various colors you may see in each bead
Brown: Anxious, nervous, fearful
Black: Stressed, tense or feeling hurried
Grey: Extremely nervous or anxious, scared
Amber: Slightly nervous or anxious
Green: Neutral reading, normal, not under great stress
Blue-green: Emotionally charged, somewhat relaxed
Blue: Relaxed, At ease, calm, lovable
Dark Blue/Purple: Very happy, in love, passionate, romantic