10/15 years ago Copperfield did a card trick with the complete audience. Every spectator had on their chair a sheet with cards printed on it. The audience split us the sheet as asked to finish with 8 cards - 7 cards the same and one 'odd' one.
I used to perform this trick but unfortunately I have forgotten the exact method.
The effect is as follows; 
The audience is asked do as Copperfield does. To shuffle the cards as desired, then there is a series of counting up and down the cards and returning the deck and then recounting again., etc, ... and at the end when they return the last card they all hold in their hand the same 'odd' card.  The only one that is different from the seven other cards. Just like Copperfield.

This is obviously a mathematical card trick but I am not able to find the method anywhere. 
Does someone have some information about this trick? If so it would be much appreciated.
You can contact me directly at: astleyrc@hotmail.com

The trick is called the "Moon Card", and it consists of 8 blank cards and 1 odd card. It's a variation of the 21 card trick.

The trick is called the "Moon Card", and it consists of 8 blank cards and 1 odd card. It's a variation of the 21 card trick.