I have a little safe that I use to store powders. I keep a set of spare keys in that safe.
The keys are starting to be coated with something white / silvery.
Could one of the tins of powder be decomposing ?
I opened a container of IMR powder a couple months ago to see how much was in it, and I recall a very fine dark haze oozing out the open top. If I wasn't wearing glasses at the time I would not have noticed it.
I'm guessing that if I locate the offending container, the burn rate of that powder will be changed.
Thoughts ?
From a jewellery background I would guess that the white/silvery substance could be due to acidity, or a chemical reaction of some kind.
The dark haze - is it the same that we I know so well from the old Somchem tins? They almost always have a slight dusty cloud leaving the opening.
I've been given powders that date back to the 80's and all of them have been perfectly good except for one tin of Musgrave S200 which was MS200 with different branding. It was rusty inside and out and the powder smelled very noticeably odd. It seems to me that as long as the interior of the container is sound that the stuff seems to last pretty much indefinitely. I would be unpleasantly surprised to find that it's powder coming apart chemically. If it is it would also require the containers to be permeable assuming they are properly closed and that seems especially unlikely.
Have you got anything else stored in the safe?
Nothing else. Powder, and the keys.
I'll open each container and visually check the powder to see if anything is obviously off.
Quote from: big5ifty on Mar 17, 2025, 06:24 PMNothing else. Powder, and the keys.
I'll open each container and visually check the powder to see if anything is obviously off.
Nothing I can see.
The residue on the keys is a very fine grey and wipes off easily. There is a thin build-up of brown rust on the bottom quarter of the door. There is an aluminium item on the keychain which is not affected, indicating it may be something as simple as humidity. These last few months have been unusually humid, we normally at 25%, it's been 50-70% for consecutive months now.
That can explain why it's never happened before - it's never been this humid for so long before.
That makes sense to me. It also gives me cause to open a long gun safe that I haven't been in for at least 6 months. Hope I don't find a nasty rusty surprise.
Humidity is the most likely culprit with electrolysis occurring on a micro scale because of it's increased presence.
Most modern keys are made of a really shitty (whatever is cheapest) alloy these days, try bend one, they can not bend, they just break showing a very grainy material.
I have a lot of keys in use, perhaps as many as 30. I have noticed that my 40 year old front door key is still good, but the one I bought my wife 17 years ago has been replace perhaps 4 times already, same with all the old doors, keys are still good, but the new doors locks and keys are replaced every 2 - 3 years, worn out.
My locksmith sais that we can not get proper metal keys, they just not made anywhere anymore, just the alloy type.
When you have a bunch of keys of different manufacturer and age, they react with each other on a minute scale.