Mood rings have been in vogue since 1970s, most common among teenagers. The way mood rings function is based on the body temperature, i.e. as the body changes its temperature the ring changes its color. Mood rings function on the basis of our body temperature; the liquid crystal present in the mood rings moves when the body changes its temperatures and this fluctuates the light that is r eflected and this causes the ring to change its color.
Mood ring is a jewelry; specifically a ring that supposedly alters its color according to the state of mind of an individual wearing it. The term mood ring was coined by two visionaries Josh Reynolds and Maris Ambats who invented mood ring by bonding liquid crystals and quartz stone into rings almost 30 years ago in 1975. Mood rings contain thermo chromic substance which has property to change color according to change in temperature. This liquid crystal is filled in capsule shaped faux gemstone usually made up of Quarts or glass.
The body temperature is conducted from ones fingers to the liquid crystal present inside stone of the mood rings; this body temperature varies according to the state of mind of the person. As temperature varies the molecules of the liquid crystal tend to absorb and reflect light wave at different wavelength and this change in the structure of molecules of liquid crystal change the color of the ring too.
Basically, it is nothing but a chemical reaction at molecular level which results in change in wavelengths of light waves, responsible for the change in color of liquid crystal present in the mood rings. So when a person is delighted or happy, the skin blushes due to increase in flow of blood towards skin causing the temperature to increase which cause the mood ring to change its color to blue, as at mildly higher temperature the termochromic liquid crystal stone reflect blue color. A Mood ring can turn into several colors – Black, White, Gray, Shades of Green, Shades of Blue, Shades of Red, Shades of Purple, Shades of Yellow and Shades of Brown.
Liquid crystals are the secret to the mood ring’s changing array of colors. Liquid crystals are extremely sensitive to heat and will reflect different wavelengths of light in response to rise or drop in temperature. These different wavelengths get reflected to our eyes as different color. The position of the crystals determines which wavelengths of light are absorbed and which are reflected back to us, and that is what makes the stone appear to change color.