master materia stuff?

[BG-57]

When you beat Emerald weapon, you get master summon, master command, and master magic, right?

Correct, you get one of each.

What about the support and independent, do they not have master summons?

Again correct, they cannot be blended into Master forms.

Also, if you get the master materia from Bugenhagen, and then you beat the Emerald weapon, do you have 2 copies of each?

You get one of each from Emerald, but Bugenhagen's observatory will give you as many of each kind as you are willing to master the component individual materia for. But it's very time consuming to master a full set even once, even with Triple growth slots and using the Northern Cave to level it. I leveled up each set twice and defeated Emerald so I eventually had three Master materia of each type.

I am interested in this because I am currently playing VII and I would like to obtain the master materia this time around.

I found it worthwhile.