Got rid of the best diamonds, receiving old money (10)

'got rid of' is the definition.
('eliminate' can be a synonym of 'get rid of')

'the best diamonds receiving old money' is the wordplay.
I cannot quite see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
'best' could be 'a' and 'a' is found in the answer.
'diamonds' could be 'd' (abbreviation in bridge say) and 'd' is found within the answer.
'money' could be 'm' (abbreviation used in economics) and 'm' is present in the answer.
This explanation may well be incorrect...

Can you help me to learn more?