Possible Clues:

• Smooth as it turns by the minute
• Lustrous metallic lining, for example
• Has the smooth South got a 12 across end?
• As it turns very small and very smooth
• Sanity (anag.)
• Like it turns with a very small shine
• For what's so smooth, just a very little bit at the end (6)
• Of the South just a very little bit is so smooth
• Smoothly finished a little after second
• Can say the cover is smooth and shiny