The last major bonus in the Gem Finding 40/40 in the Shaping sub-specialization is bugged.
It reads " You now have a chance to uncover an Ambivalent Amber as an additional byproduct when prospecting."
With my current built of having 20/20 in each sub-specialization of Gem finding (Emerald, Onyx, Ruby and Sapphire) I can no longer receive an Ambivalent Amber from prospecting.
After prospecting thousands of ores I have not received a single Ambivalent Amber as a byproduct.