Malaysian capital invested in less rounded gem (8)

I believe the answer is:

sparkler

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'gem' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for sparkler that I've seen before include "Jewel" , "Firework - precious stone" , "Eg, a diamond" , "Bright gem" , "Possibly brilliant" .)

I've seen this clue in The Guardian.

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