Probably mint then. Nothing else smells like mint
But it doesn't look like mint to me so hold back on the mint sauce til it grows a bit and maybe flowers
I do have hayfever at the moment, so I may not be smelling things quite as they are
Is it possible that it is a form of Salvia? Not exactly minty, but the leaves do have an aroma when crushed.
I'd go with Lemon balm Melissa officinalis. Those pointy thick crinkled leaves look typical to me.
If I'm right the crushed leaves will give off a sweet lemony scent.
You can make a delicious soothing lemony tisane from pouring boiling water on the leaves - really good at bedtime ....... if I'm right
Thanks everyone! Have potted a couple up and will see what happens. The leaves got somewhat obliterated (my fault) but the stems are healthy, so hopefully they'll do ok