how can we chemically make silver articles black or tarnish them?

Answer 1

Of course, it is a chemical reaction that causes ths to happen naturally.

Expose the silver article to sulphur. SO2 would do the job most admiarably. Dipping it in egg yolk too - it is the sulphur that does the job.

Answer 2

I at times use a tarnishing or a blackening agent to highlight pattern work on my silver pieces.

Liver of sulfur, which normally comes in small pellets that you dissolve in warm water, is a common tarnishing agent used on silver. I like to use liver of sulfur at a relatively cool temp, dip the jewelry item for a few moments, rinse it in a cool bath, and repeat. I repeat the dipping and rinsing process several times till the "antiquing" is what I want to see. I find by doing it this way I get a wider variety of hues and a more interesting patina.

For a black antiquing look, I use "Background Antique" by VIGOR. I apply it with a small paintbrush and have running cold water immediatly available to stop the blackening process.

Both items are available from any number of jewelry-supply houses. I use Otto Frei--a reputable company; see the link below.

Answer 3

tarnishing of silver is due to a chemical reaction involving sulphur.
hydrogen sulphide reacts with silver to form sulphide of silver and that is the eason of tarnishing.
suppose if u dip a silver coin in boiled eggs and keep it there for some time, u can see it has turned black.it is becuase egg contains hydrogen sulphide.
silver is normally treated as an inert metal ,like gold. but rarely we can see silver also rusts when kept in air for long time due to the presence of hydrogen sulphide in air.
hydrogen sulphide is not present in the atmosphere as such, but sulphur in the atmosphere from automobile and industry exhaust can give rise to H2S.

Answer 4

YOU CAN PUT THE Ag METAL IN A GAS JAR CONTAINING SULPHUR OXIDE GAS(SO2)
AND IT WILL TURN BLACK AFTER A WEEK OR 2