Should I give rank up gem priority over materials

I have a 7* silk and I also have saga R1 to R2 gem
But I also have enough materials for her to reach R2 naturally
So what should I do?

Comments

Personally, I use mats if I have them & save gems for times I need a champ & don't have a way to get the cats I need

Use the gem bc then you keep your mats and can R3 easier