Sahasrara

The crown chakra is the seventh chakra.
Located at the top of the head, it gives us access to higher states of consciousness as we open to what is beyond our personal preoccupations and visions. The function of the Crown chakra is driven by consciousness and gets us in touch with the universal. The Sanskrit name “Sahasrara” is sometimes used to designate the seventh chakra. It can be translated as “Thousand petals”.

The seventh chakra is referred to as:

Crown chakra
Sahasrara
Shunnya
Niralambapuri

The crown chakra is most commonly represented with the color white, although it can also be depicted as deep purple. The auric color of crown chakra energy can also be seen as gold, white, or clear light.

The symbol of the Crown chakra is composed of:

A circle
A thousand petals

The dominating color of the crown chakra symbol is white. Its petals are multicolor, like a rainbow. The circle is sometimes compared to the symbol of the full moon.

The most commonly accepted location for the seventh chakra is at the top of the head or slightly above the head. It sits like a crown, radiating upwards, hence its name. The Crown chakra is primarily associated to the pituitary gland, and secondarily to the pineal and the hypothalamus. The hypothalamus and pituitary gland work in pair to regulate the endocrine system. Because of its location, the crown chakra is closely associated with the brain and the whole nervous system. Note that energetically, the seventh chakra has a connection with the first chakra, as they both are at the extremities of the chakra system.

The crown chakra is associated with the following psychological and behavioral characteristics:

Consciousness
Awareness of higher consciousness, wisdom, of what is sacred
Connection with the formless, the limitless
Realization, liberation from limiting patterns
Communion with higher states of consciousness, with
Ecstasy, bliss
Presence

The crown chakra is associated with the transcendence of our limitations, whether they are personal or bound to space and time. It is where the paradox becomes norm, where seemingly opposites are one. The quality of awareness that comes with the crown chakra is universal, transcendent.

As we are immersed in the energy of the crown chakra, we feel a state of blissful union with all that is, of spiritual ecstasy. This chakra allows access to the upmost clarity and enlightened wisdom. Some describe this chakra as the gateway to the cosmic self or the divine self, to universal consciousness. It’s linked to the infinite, the universal.

When the Crown chakra has an imbalance, it can manifest as:

Being disconnected to spirit, constant cynicism regarding what is sacred
On the opposite side, an overactive crown chakra could manifest as a disconnection with the body
Living in your head, being disconnected from your body and earthly matters
Obsessive attachments

HOW TO OPEN YOUR CROWN CHAKRA

Sit down by crossing your legs
Lay your hand before your stomach.
Allow both your little fingers point towards the up and being away from your body, touching at their tops and cross the rest all fingers with the left thumb underneath the right ones.
Get all your concentration towards the crown chakra and the area where it lies, i.e, the crown of the head.
Now you need to chant the sound "NG". But make sure you are doing it silently, softly and clearly.
Also keep in mind, during this entire procedure your mind is at absolute peace and you are totally relaxed at your body.
Remember, this meditation would take not less than 10 minutes. Perhaps this is the longest meditation.