They stretch credulity to the extremes in my view.. My initial response was. I have never seen such fake nonesense in all my life..

Imagine a Crystal providing a link to any time and and any space...

Then I looked at silicates like quartz a little more closely wondering about how "virtual" (though some see them as alternative) realities are accessed every day using a very high grade quartz, viz a viz Liquid Crystal Displays or LCDs as we call them.. Silicon chips and micro processors all using Quartz to take ones awareness away from the physical body.

When i thought of the properties of crystal in this way. I found i could not be 100% dismissive of the eperiments shown in the videos above.

Anyway .. where was I ?

Micro calcite Crystals in the Pineal. Possible

Melatonin with a dribble of our very own DMT equivalent secretions. Also Possible

Brain frequency alteration to extend our receptivity(picking up other stations)....Opening to Channel. Possible too.

I cannot say which one exclusively is responsible for our dreams, Out of Body Experiences, Non Proximal Hearing, Channeling.

Like as not, I suspect a combination of all them in varying degrees is responsible