They are natural indigo.
These are sooooooo dope.
http://www.nakedandfamousdenim.com/blog/photos-of-faded-jeans/
I have a pair with about 3 months on them. Not much fading at all. It takes a long time to get them to fade like that. I actually contacted the guy who owns that pair that you posted and he said he washed around every few months. I don't really like when my denim gets soft so that wasn't reall an option for me.
