Newbie question. Where is the Rubysilver ore?

It's me again from another post with Cobalt ore. I have been looking for ruby ore for like 7-8 hours now with no avail. I have checked these locations in normal difficulty.

Ruined castle south-west caves with waters and zombies for 5-6 times but don't find any ore.
Running around goblin cave so many times on F1.
Die and speculate players on Goblin cave F2 for awhile.

So can anyone pinpoint exactly where it is? only need a few for Armorer quest to upgrade Squire gear.