I find interesting that it is was not a old-stock remnant from old Tetenal but a product from Tetenal 1847.
(But maybe it was old stock and just got a safety-data sheet with new name on it.)
Based on an answer to my question received from Wolfgang Moersch, I suspect his MT10 gold toner might be closer to the Tetenal product than his MT6 is:
@Sal Santamaura You are correct - MT6 is the very different Nelson's Gold toner - of which I have a bottle in front of me in my darkroom as I type this. MT10 and the Tetenal product are pretty standard issue gold & thiocyanate toners as far as I can tell - which are hardly difficult to mix, apart from the excruciating price of gold chloride.
Based on an answer to my question received from Wolfgang Moersch, I suspect his MT10 gold toner might be closer to the Tetenal product than his MT6 is:
Good point. I just scrolled down his list of toners until I found a goldtoner, and just one. I did not expect several positions further down, out of sight, a second goldtoner to show up.