Diamonds, perhaps, and gold for one seeking hand (6)
I believe the answer is:
suitor
'one seeking hand' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'diamonds perhaps and gold' is the wordplay.
I cannot quite understand how this works, but
'diamonds' could be 'suit' (diamonds is a playing card suit) and 'suit' is found in the answer.
'gold' could be 'or' ('or' is the heraldic name for gold) and 'or' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'for' acts as a link.
Can you help me to learn more?
(Other definitions for suitor that I've seen before include ". . . he woos his girl" , "Wooer" , "It's our (anag) - admirer" , "A man wooing" , "Man pursuing a woman for marriage" .)