Blue eye.

A nazar (Turkish: nazar boncuğu Old Turkic: gökçe munçuk) is an eye-shaped amulet believed to protect against the evil eye ("evil eye", from nazar and "amulet" from boncuğu). The word "nazar" is derived from the Arabic نظر, "sight" or "seeing". In Turkish, it is called Munçuk. In Central Asia, during the ages of Tengrism, people held similar superstitions like horseshoes, garlic, wolf's tooth, dried thorn, lead, stones; but the crystal blue eye has always been the most popular one.

Cappadocia (Kapadokya). Nevşehir Province. Turkey