Hamster, you're an adder - I recommend picking up a Gridanian Doublet from the Order. The +20 Output will generally do it for you, but feel free to tweak with other things like gloves for a few more points to get the extra attempt if that doesn't do the trick.

This isn't tested, but I've got the feeling that it's around 25-ish in output.

But maximize Gathering before you maximize Perception once you start mining in Grade 5 areas - chance of success isn't something you want to neglect.