Moodrings 4mm BESTSELLER (our best-selling item, we sell 120,000 pieces annually)

A mood ring is a ring that contains a thermochromic element, such as liquid crystals. The ring changes color in response to the wearer's body temperature. The color is used, by some proponents, to indicate the emotional state of the wearer. The mood ring was invented in 1975 by two New York inventors, Josh Reynolds and Maris Ambats, who combined bonded liquid crystals with quartz stones in rings. They initially retailed for $45 for a "silver ring" and $250 for a gold one. They became more of a craze in the 1970s. A mood ring is a specialized liquid crystal thermometer, wearable on the finger. The ring is usually adorned with a faux gemstone (usually made of quartz or glass) that is either a clear capsule filled with thermochromic liquid crystals, or has a thin sheet of liquid crystal sealed underneath. Changes in temperature cause the crystal to emit different wavelengths of light that changes the color of the stone. The liquid crystal used in the mood rings is usually set up to display a "neutral" color at the average human skin temperature, which is about 37°C. The theory behind the idea that the ring indicates the wearer's mood is based to a claim that body heat fluctuates with the wearer's emotional state. Human body temperature is known to vary by small amounts (less than 0.5 °C) through circadian and menstrual cycles and when the body is fighting an infection. Variations in air temperature seem to have a greater effect on the ring's temperature than changes in the wearer's body temperature. No direct correspondence between a particular mood and a specific color has ever been substantiated.