Level 3 Mine Blueprint

[Trickname]

So I completed the achievement to collect 500 stones however the vendor in my garrison doesn't have the blueprint. Has anyone else had this / know how to get the blueprint?

[Kaesebrezen]

Is your Garrison Tier 3? You can't build T3 buildings unless you have T3 Garrison.

[Icebear]

Isn't it just autolearned when you get the achievement?

[Trickname]

Is your Garrison Tier 3? You can't build T3 buildings unless you have T3 Garrison.

Thanks, wasn't aware this was the case.