Skeleton

[JackDunwoody]

16A Stone jar with a little mental inside (5) ?N???
6D Last rose's last thorn, perhaps (4). R??E

[dannyk13]

Granite - ni(metal) inside grate(jar)
Rune - run(last) + (ros)e

[JackDunwoody]

Thanks Danny but I have the second letter in 16A as N

[dannyk13]

Where have you got the 'n' from.The clue has seven letters?

[JackDunwoody]

Thank you Danny. I've got only 5, so I've added a black square too many!