Lifted cloak covering item with 50% off in Institute of Clay (10)

'lifted cloak covering item with 50% off in institute of clay' is the definition.
I can't tell whether this definition defines the answer.

'lifted cloak covering item with 50% off in institute' is the wordplay.
'lifted' is a reversal indicator (going up in down clue).
'covering' is an insertion indicator.
'with 50% off' means to take half the letters.
'institute' becomes 'i' (common abbreviation as in MIT).
'item' cut in half is 'it'.
'it'+'in'+'i'='itini'
'cloak' going around 'itini' is 'citiniloak'.
'citiniloak' in reverse letter order is 'KAOLINITIC'.

Can you help me to learn more?