Start from the top of Flail Out or the top of the 1st pitch of Gemstone. Follow a left facing dihedral to where it's crack pinches down (crux) just below a large chockstone. Work up past the chockstone to bolted anchors shared with Gemstone route.
Double rope rap with 60 meter ropes gets you to the ground. Two raps with a single 60 meter rope works well when using a huge intermdiate horn right at the tail end of the rope strands. The horn is slung with a loop of rope inside dull-green tubular webbing.
The rating of 5.6 comes from Barry and Rita Loucks' guide. I felt like the crux was more like 5.7, albeit only a couple moves.
Christian Crack is in a left facing dihedral just west of the 2nd pitch of Gemstone. See a marked-up version of a photo from Monomaniac on the Gemstone West page.