F# Card Shuffle function

I've been trying to create a simple card game in F#, i have created a simple randomizer function using system.Random.

type card = int
type deck = card list
let rand : int -> int = let rnd = System.Random ()
                        in fun n -> rnd.Next (0 , n )

However my problem is that i don't know how to create a shuffle function deck -> deck,using the rand function.

Any help is wanted.