For the triantanium there could be an Alien/Quantum triantanium refinery and for the antanium an Alien/Quantum antanium synthesis lab.
There is no argument in having that. And it would make triant no more valuable. What makes its value is the difficulty of production... We can't have an alien building for each resource, we need some to be hard to get otherwise there is no point in getting it and it would be too easy.