The most common and most likely answer to this crossword clue is the 5 plus 1 letter word OBJET D
I've seen this crossword clue in The Times
O
B
J
E
T
D
More clues leading to the result OBJET D
Buddy explains!

The straight part
We know that "Decorative item" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case decorative item = objet d.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.