Crystal ball quartz better than natural crystal?

First, Quartz is a natural crystal, and yes they are better than say a glass (manufactured) crystal.

Natural crystals usually have inclusions (small inner flaws and other materials within them) these give your eye and mind something to focus on and you are more likely to achieve the needed state of mind you do your scrying in.

I have know others who use other types of natural crystals including rose quartz, amethyst, onyx, and a lovely piece of amber. They each swear they have better luck with their crystal than with others, so try a few and see what works for you.