The 'stone' of a mood ring is really a clear dome containing thermotropic liquid crystals. The crystals respond to changes in temperature by twisting. The twisting changes their molecular structure, which alters colors that are absorbed or reflected. So when the temperature of the liquid crystals changes, so does their color.

Mood rings can't really tell your emotions, but the crystals are calibrated to have a pleasing blue or green color at the average person's normal resting temperature. When you are excited or stressed, blood flow is directed away from the skin...

All sterling silver will over time tarnish (darken) as it is exposed to the air. Simply use a polishing cloth, as gentle rubbing and buffing alone will remove tarnishing. Polishing cloths are ideal as they are impregnated with a polishing compound, last a long time and give an amazing shine.

Sterling silver is best stored in a cool, dry place (heat and moisture speed up the tarnishing process), NOT in your bathroom! Try adding a piece of white chalk to your storage area.

I do not recommend you use any jewelry cleaner on mood jewelry as this will damage the stone.

I have been selling my mood rings for 7 years and have had one customers finger turn green. Certain metals can turn your finger green due to a combination of the metal and the acids in your skin. Sterling silver is 92.5% pure silver, with the remaining 7.5% made up of other metals, usually copper. Some people react more to copper than other people, due to a chemical reaction with moisture on your skin and the alloys in the metal.

Even silver & gold jewelry can produce a reaction in certain people. If you are one of them, you will greatly reduce the chance of any ring turning your finger green if you take care to keep soap, lotions & other chemicals away from your ring. Remove your rings before bathing or swimming, especially in saltwater.

Sizing can be tricky! I sell an accurate ring sizer you can use over and over. https://www.etsy.com/listing/642063241/ring-sizer