  The augmented Iwasawa algebra of a p-adic Lie group is a generalisation of
the Iwasawa algebra of a compact p-adic Lie group. We prove that a
split-semisimple group over a p-adic field has a coherent augmented Iwasawa
algebra if and only if its root system is of rank one. We also characterise
when certain solvable p-adic Lie groups have a coherent augmented Iwasawa
algebra.
