Pottery in horse-drawn Russian carriage (6)
I believe the answer is:
troika
This clue is a triple definition!
'pottery' is the first definition.
(pottery made by the Troika group)
'in' acts as a link.
'horse-drawn' is the second definition.
(I've seen this before)
'russian carriage' is the third definition.
(I've seen this before)
(Other definitions for troika that I've seen before include "Russian three-horse coach" , "Russian vehicle pulled by three horses" , "Russian horse-drawn vehicle" , "Threesome" , "Russian carriage pulled by three horses abreast" .)