Grease is not to be used in the lower end of the 1911. It will gum things up as you discovered.
It works great on the top end though, (frame slide and barrel).
I use "Slide Glide" by Brian Enos, and have had good results with it.
The black color comes from unburned powder and is lubricating in nature (ie: graphite) and doesn't negatively affect the grease (however it looks awful )
Use it on the top and bottom locking lugs on the barrel, bushing, frame and slide rails and the upper locking lugs in the slide. Also, recoil spring, guide rod, etc...