www.925-1000.com

I am the lucky owner of those two roundels of Chellini Madonna.
The original rests in Victoria and Albert Museum in London
but those two, copies in silver, are mine:


In fact I like them as they are: the first one heavily patinated
and the other cleaned partially by the previous owner.
It is the contrast which does appeal to me and I would like it preserved.

Needles to say, I do not intend to part with any of them in this life,
they hang in separate rooms and are meant to be enjoyed in different times of the day.
So how to go about suspending the animation of those things,
how to ensure they do not age further?

As an arriviste and a barbarian at heart
I have recommended elsewhere the use of the translucent nitro lacquer car spray- but even I cannot be driven to such a barbarity in this case.

But what about applying translucent layer of Cr2O3?
It is done by dipping in a warm bath consisting of thiosulphate(ordinary fixer in the photography) and a certain potassium or sodium compound of chromium, a poisonous substance so I will leave the details out here. Has anybody tried it?
Any advice keenly anticipated.
.

before you poison the countryside with noxious vapours why don't you look into vacuum-sealing?

you are considering spraying automobile products on your silver so you shouldn't object to vacuum-sealing, it preserves the silver without harming it - or yourself.
(if you want to see how badly auto products can damage someone, look at poor priscilla presley. her argentine cosmetic surgeon injected automobile lubricant into her face - he's been charged)
.

kerangoumar, point taken.

I wish to report to this Learned Society that the scientific experiment
is in progress now. Have obtained a nylon bag lined with the polymer,
activated coal and a copper ion exchanger. (Lucent technologies product)
To this bag all of my 12 antique chargers went but not a set of 6 dessert plates. Simply there was no more room. I will report on advantages and dis-advantages of such a controlled environment method of storage in a year's time.
That is unless I drop dead or go bankrupt, which would be a pity.
.

Wonder if this guy lived through the process...:P