Noble metals
Yes, palladium is about the same price per unit.
But there's a lot more of it -- supply & demand, as so much goes into catalytic reactors.
If we were using platinum in those amounts, it would go back to where it was in the late Sixties: palladium roughly 1/10 the price of platinum. I.e., $4K for platinum...
Therefore they try hard to cut the amount used.
Regards,
Ric