I have found a mystery and not sure how to solve it.
In the northern part of Waking Shores, near Scalecracker Keep, there is a basalt (dried magma rock) jetty and within it a Dimmed Forge. When you click on the Dimmed Forge it says “This forge longs for the touch of a Blacksmith”
So I tried upgrading some ores near it, but that didn’t work. Maybe I need to smith an item here like a sword or armor?
Solution (Spoilers):
***Update:***Crafted a Primal Molten Alloy using the Dimmed Forge and in the Slack Tub below it gave a Glimmer of Blacksmithing Wisdom. (Increases Blacksmithing knowledge by 3)
Appears to be repeatable.
Reference images:
imgur. com/a/ee9KDQ3
Co-ordinates 56.64, 19.65