Come down by gold carriage (6)
I believe the answer is:
landau
'carriage' is the definition.
(type of horse-drawn carriage)
'come down by gold' is the wordplay.
'come down' becomes 'land' (to land is to come down after flying).
'by' says to put letters next to each other.
'gold' becomes 'au' (Au is the chemical symbol for gold).
'land'+'au'='LANDAU'
(Other definitions for landau that I've seen before include "Horse-drawn carriage or car with folding top" , "A four-wheel covered carriage" , "Four-wheeled vehicle with two folding hoods" , "Old-fashioned four-wheeled covered carriage" , "An auld type of carriage" .)