Invention of the Mood Ring
In 1975, jewelry designer Marvin Wernick accompanied a physician friend to an emergency and marveled when his friend applied thermotropic (meaning, changed by temperature) tape to a child’s forehead to take her temperature. Using this premise, he took a hollow glass shell and filled it with thermotropic liquid crystals. He then attached the glass shell to a ring so that when worn on the finger, the thermotropic material would change temperatures and color.
Failing to patent the idea, Wernick missed an opportunity to ride the wave of the new fad as Joshua Reynolds was the first to popularize the rings. Reynolds envisioned the mood rings as “portable biofeedback aids”, and managed to sell $1 million worth of them in a three month period in 1975. Even so, Reynold’s company went bankrupt, victim of a flooded market of imitations.
Mood rings became very popular during the 1970’s and for a few years, were considered a serious piece of jewelry. The mood ring fad peaked in the late 1970’s and are now seen as an icon of the 1970’s culture.
How Mood Rings Work
Thermotropic crystals respond to changes in temperature by twisting. The twisting changes the molecular shape of the crystal which alters the wavelengths of light that are absorbed or reflected and hence causes the crystal to change colors.
Mood rings can’t tell your emotional state with any degree of accuracy, but the crystals were calibrated with have a pleasing blue or green color at the average person’s normal resting peripheral temperature of 82°F. As the body temperature increases, which it does in response to passion and happiness, the crystals twist to reflect blue. When you are excited or stressed, blood flow is directed away from the skin and more toward the internal organs, cooling the fingers, causing the crystals to twist the other direction, to reflect more yellow. In cold weather, or if the ring was damaged, the stone would be dark gray or black and unresponsive.
The inside of the mood ring conducts heat from your body to the thermotropic material
What the Mood Ring Colors Mean
Due to fluctuations in the making of mood rings by various companies, interpretation of mood ring colors are not universal. The top of the list is the warmest temperature, at violet, moving to the coolest temperature, at black.
violet blue – happy, romantic
blue – calm, relaxed
green – average, not much going on with you
yellow/amber – tense, excited, unsettled
brown/gray – nervous, anxious, strained
black – cold temperature or damaged ring