The bottom I knew was going to be a pretty simple solution. We had some extra lengths of the finished white oak quarter round molding. This was a simple trim job nothing special, 4 or 5 standard cuts and it was finished. Tacked to the floor with a brad nailer and the base was finished. (well almost, still need to mix up some mortar to fill in the void between the rock and oak quarter round, but that's for another day.
The part of this fireplace trim project that ended up taking the entire day was the stacked crown molding I decided to use for the top part of the fireplace. I needed to build a base on the ceiling because the floor joist for the second floor were left 4 inches away from the stone (per code.) This meant there was nothing to tack the crown into on the top. I used a standard 3 inch base molding and laid it flat on the cieling, and with a generous amount of consturction adhesive, I was able to afix it to the ceiling (I used some nails as well - not sure if they realy are helping or not, but I felt better.) Next the crown mold was going to go up against the base and against the stone fireplace back. This is where the problems started.
There were a few problems the first of which was my own ignorance. The first time I did crown molding I think I got lucky with the angles - everything worked fine. This time, the moldings spring angles were not the same and thus I didnt get as lucky. After spending about 4 hours and cutting through 16 feet of molding I finally sat down and did some research. (with some thinking juice.) What I learned is that based on the spring angles of the molding the miter and bevel angles change - old dog / new trick. This miter / bevel chart was extremely helpful: http://www.installcrown.com
The second issue (which ultimately the caulk came to the rescue with) was the uneven surface of the rockes and unusual angles it creates. In one are I chewed away the back of the crown molding so it would sit against the stone a little better. All in all it came out -- ok. I had one corner that I had to use a generous amount of caulk to 'mend' it.
