Crumbledore

There's a lot of great limestone on Tucki Mtn, but this ain't it. For being a canyon through crumbly slate, it's actually pretty decent (For being a canyon through crumbly slate being the operative term).

Hike up the ridge west of Mosaic, eventually take a sheep trail off to the right over the top of a little drainage and over a ridge to the canyon. You'll see another fork of Crumbledore a little ways further, which is quite possibly the crumblier of the two.

The first couple downclimbs really set the tone for the whole canyon. Then there's a 150ft free hang rappel with blocks to kick loose, a shorter rappel that's kind of cool, and a 150ft free hang rappel with blocks to kick loose. That puts you to the confluence, with mostly shorter rappels as you go down from there.