Does having greater magic find or gold find affect the quality of the gems dropped? If I have a decent amount of magic find and a monster was going to drop a Chipped Ruby, is it possible for the magic find to update it to a Flawed? Or it is based solely on the difficulty level you are on and the static drop rates of gems?
Gems are not magic items (their names are in white, not blue/gold/green), so increased chance to find magic items does not affect them.
In Diablo 2, increased MF did not affect gem drops, and I haven't heard anything about this changing in D3.
This need more tests, but you can follow the main idea. Magic find does not increase the drop chance for gems.