The nazar 🧿, also known by many other names in other cultures such as mati or mal de ojo, is an amulet said to ward against the "evil eye" and negative energy. It collects negative energy and breaks upon too much.

The amulet is traditionally made of banded glass in dark blue, white, light blue and black, in that order, to resemble an eye.

https://en.wikipedia.org/wiki/Nazar_(amulet)