Mystery Spots/Marks/Stains?? On Hands

Good Morning All, I have developed these spots/marks/stains on my hands over this past week with the spots starting out as brown then going fully fledged black. I did make up some 0.05M Silver Nitrate from 0.5M about 3 weeks ago so thought that might be why but they only appeared this week and I was double gloved up when making it and haven't touched the bottles since, all surfaces had been wiped down while wearing gloves. The ones on my finger tips appeared on Wednesday when I was gloved up cleaning through a cupboard with no chemicals in so I have no clue at all what could have caused this. Any ideas??


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Oh no! GOOD GOD NO!!!

That looks like Silverus Nitrosis.

Silverus Nitrosis - Wikipedia

Wikipedia › wiki › Silverus_Nitrosis

Silver nitrate is the least expensive salt of silver; it offers several other advantages as well. It is non-hygroscopic, in contrast to silver fluoroborate and unfortunately skin contact results in Silverus Nitrosis. Dark spots/marks/stains manifest which if left untreated, will spread to the brain and cause you to want to become a teacher. The only documented cure is to amputate the hand as soon as possible.
Time to live handless :laughing: :laughing:
Yes, silver nitrate will find your fingers even if you think you have taken all reasonable precautions! It does fade and disappear after about a week.

Dino Girl

My Bite is worse than my Bark.
I had the same - it's probably some Silver nitrate crystals on the bottom of your cupboard.

I got mine from a dry petri dish.


Staff member
Site Admin

Again @Emil Tac I appreciate this is a bit of fun, but when someone searches "silver nitrate preproom" and gets some of this as a search result, it appears as though we are offering bad advice here, which if it happens a lot, can cause us big issues in terms of web filtering in schools.

Recently we had an issue in several schools who could not access the site because someone had added a single phrase which provoked a safeguarding response from the county filters. This then meant 100 or so technicians lost access for a week and had we not realised, it would have affected more schools in time.

I don't want to come across as a party pooper, but forums are really delicate, especially ones that cater for schools and it just takes a handful of posts to kill them completely.