Shiny silver key found in belt (6)

I believe the answer is:

agleam

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'shiny' is the definition.
(agleam means gleaning or shining)

'silver key found in belt' is the wordplay.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'key found in belt' becomes 'leam' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ag'+'leam'='AGLEAM'

Can you help me to learn more?

(Other definitions for agleam that I've seen before include "Sparkling" , "scintillating" , "Shining brightly" , "Bright" .)

I've seen this clue in The Times.

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