Porcelain box silver glazed, qianlong mark

[damyp]

Hello,

Got this porcelain box, height 12cm diameter 25cm.
It is not silver or bronze metal but indeed a glaze replicating silver that I never found before.

Could it be of the period? Have you already seen something like this?

Here are 6 pictures:
ibb.co/YRP0dhm
ibb.co/N7Wp4qT
ibb.co/MCHrk1Y
ibb.co/P90XDZT
ibb.co/LpSc7cH
ibb.co/6rGCZZw

Than you!

[peterp]

To my knowledge there never has been such a glaze. If it were not for the inside, I would have thought it is some laquer ware box was coated. Is the inside real porcelain or some kind of enamel?
Just regarding the mark, marks are usually applied last and they don't look this way if made by hand.