[vmelkon]

There are threads about making gold but that would be difficult.
How about converting calcium to scandium?
How about converting tungsten to rhenium?
Zinc -> gallium?
Bromine -> krypton?

[gippgig]

Sure, any of these could be done. However, it simply isn't economical. Isolating the desired product from radioactive byproducts costs far more than the product is worth.

[shelanachium]

What about the ruthenium, rhodium and palladium formed in nuclear reactors? Are these ever separated from the waste and marketed? - they are pretty valuable. No isotope with half-life more than a year is formed, and most are much shorter.

Ru, Rh and Pd from this source could cause problems in studies in which their atomic weights matter - these would differ from those of the natural elements.

[vmelkon]

Sure, any of these could be done. However, it simply isn't economical. Isolating the desired product from radioactive byproducts costs far more than the product is worth.

It should be economical. Ruthenium and the metals in that neighborhood are so insanely expensive.