On the Stages of Death in Tibetan Buddhism‏

The first subtle mind of death is the mind perceiving a white appearance.

When this appearance ceases, the mind has become more subtle and perceives a red appearance.

This mind again becomes more subtle and transforms into the mind of black near-attainment, to which only black appears. At this stage it is as if the dying person has no memory. Since there is no physical movement, no heartbeat, and no movement in the channels, some people think that this is the end of dying; but in fact the consciousness has not yet left the body.

The mind of black near-attainment transforms into the most subtle mind perceiving the clear light of death, a clear bright appearance like the light of dawn. This is the sign that the most subtle mind that resides within the indestructible drop at the heart has manifested and all other minds have ceased to manifest.

Then the indestructible drop opens, and its white and red parts separate, releasing the consciousness, which immediately departs from the body.

The white drop descends through the central channel to emerge through the tip of the sex organ, and the red drop ascends through the central channel to emerge through the nostrils.

When this happens it is the sign that the consciousness has left the body and the process of dying has ended.