Many rainbows appeared in the sky. On arriving, they made a big burnt offering. Kongtrül offered the serkyem, the offering to the Dharma protectors, and Khyentse, holding a vajra, sang the Lhasum Damdrak song of command to the local deities. People said (about Jamyang Khyentse Wangpo), “Something special must be happening today because Tulku Rinpoche is doing something.” Everyone was then told to recite the Vajra Guru mantra and to supplicate Guru Rinpoche. The three masters and some others went inside the cave while those who could not fit stayed outside by the opening.
As everyone chanted the Vajra Guru mantra and the Seven Line Prayer, Chokgyur Lingpa’s experience blazed. Normally you can’t reach it, but he flew up and reached the ceiling. . From the ceiling he extracted the terma box containing Dzogchen Desum. As the terma object, he took sacred medicine and nectar blessed by Shri Singha, as well as some hairs of Yeshe Tsogyal and Vairotsana. The terma box was wrapped in one of Guru Rinpoche’s garments. Chokling blessed Khyentse, Kongtrül and everyone nearby with the terma box. People now knew he was a true tertön. Chokling told them, “All who came here are most fortunate. If things work out, I have many things left to do. The kindness of Guru Rinpoche and his consort is inconceivable..” Jamyang Khyentse continued, “Chokling is a great tertön, a very precious one. His terma teaching is extremely precious, as is this place. Everyone should make offerings and circumambulations. The three of us have now opened the gate to this sacred place. When you die, you will all go to the Copper Colored Mountain -- I promise.”
pp 8-9, in The Life of Chokgyur Lingpa (PDF file)