A chest designed in a pure style (6)

I believe the answer is:

chaste

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'a chest designed in a pure style' is the definition.
I can't judge whether this defines the answer.

'a chest designed in' is the wordplay.
'designed' indicates an anagram (designed with the letters).
'in' is an insertion indicator.
'chest' anagrammed gives 'chste'.
'a' inserted inside 'chste' is 'CHASTE'.

Can you help me to learn more?

(Other definitions for chaste that I've seen before include "Set Cha up for being pure" , "virgin" , "Sachet (anag)" , "Continent" , "Decorous" .)

I've seen this clue in The Globe and Mail.

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