Wavelength: 450–485 nm
Frequency: 620–680 THz
Photon Energy: 2.64–2.75 eV

Anja (Third-Eye Chakra)
Element: Light
Color: Indigo
Sound: OM
Life theme:
This chakra is associated with your intuition, or sixth sense, and governs how the rest of the chakras function. When Ajna is functioning well, you have insight, and you trust your inner wisdom to face life’s challenges and choices. When it’s blocked, you feel close-minded, too attached to logic, untrusting, and cynical. Working on the sixth chakra opens your mind to the bigger picture and different perspectives, and it helps you receive the wisdom that cannot be seen or heard by ordinary senses.

https://www.yogajournal.com/practice/beginners-guide-chakras