The centerpiece of this tiny cut-out eye-shaped charm is a cabochon of amethyst gemstone. Amethyst is known as a healing and protective stone that calms the mind and spirit and enhances one's intuition and ability to meditate. It is also said to protect against nightmares and insomnia.
The charm is said to be protection against the 'Evil Eye', which is a malicious stare thought to bring misfortune, illness, evil spirits, accidents, diseases, insomnia, and even death.
A cabochon is an old-fashioned way of shaping and polishing a stone, usually round, before faceting (cutting) became common practice.