Great looking grips, and excellent workmanship.
Re: Micarta. Just an option/suggestion - Various Ebony species (Gabon or Macassar are fairly common) are still available, but far more expensive.
Another way, is to ebonize other common hardwoods - hard maple for example using dye.
Either method you retain the subtle color and/or grain of very dark wood.
Links:
Dyes: http://homesteadfinishingproducts.com/transtint-liquid-dyes/
Many suppliers of Ebony, here's one:
Ebony: http://eisenbrandhardwoods.com/index.php?cPath=37&&page=3
Other suppliers here: http://woodfinder.com/
I strongly recommend that buying ebony be in person, not via the internet. You need to get hands on, since there are often wide variations of color and grain, perhaps some flaws, even within a single board.