You don't go anywhere without a full charge on your mobile, so why would you go anywhere with uncharged crystals? In order to vibrate at their highest capacity, your crystals need to be cleansed and charged.
That's where a Selenite Charging Plate comes in handy. Selenite is unlike any other crystal. It doesn't need to be charged, and it will amplify the energy of all crystals set upon it.
The pure, high vibrational energy of a Selenite plate or slab is like liquid light.