Object in regalia, gold and black (3)
I believe the answer is:
orb
'object in regalia' is the definition.
'orb' can be an answer for 'regalia' (thesaurus). I'm not sure about the 'object in' bit.
'gold and black' is the wordplay.
'gold' becomes 'or' ('or' is the heraldic name for gold).
'and' says to put letters next to each other.
'black' becomes 'b' (as in pencil classifications).
'or'+'b'='ORB'
Can you help me to learn more?
(Other definitions for orb that I've seen before include "Ornamental globe" , "Ornamental sphere" , "component of royal regalia" , "ball with cross" , "Royal sphere (paired with 13 across)" .)