What encryption method should be used to have 3 trusted keys

Hey Guys,

I've been wondering about encryption lately ! I'm searching for a way to encrypt files (in any way secured enough), and then split the the key in three. The idea is that you cannot read files if you don't gather the 3 keys.

Ideally, keys should be composed of a list of words, or a phrase (some bitcoins wallet proposed this feature, to have a list of words as proof).

Do you have any idea of how to achieve this while maintaining maximum security (minimizing breaches) ?

Thanks :)!