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Author Topic: What causes silver to turn black in my home?  (Read 1853 times)

Offline thedoc

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What causes silver to turn black in my home?
« on: 06/08/2015 22:50:02 »
PEGGY asked the Naked Scientists:
What can give off a sulphur in my home that caused all my silver to go pitch black. Also burning eyes.  I did have rose spraying done in my garden on 21st May ,would that have effected inside my whole house up until now.  Surely after a rain it should have washed off.  My silver has been cleaned and is now going black again. I am also using a gas heater.

What do you think?
« Last Edit: 06/08/2015 22:50:02 by _system »


Offline SorryDnoodle

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Re: What causes silver to turn black in my home?
« Reply #1 on: 10/08/2015 02:01:27 »
What kind of a gas heater? If it uses liquid petroleum and leaks a bit, this may perhaps be the cause.

Offline alancalverd

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Re: What causes silver to turn black in my home?
« Reply #2 on: 10/08/2015 22:22:50 »
Gas leak. Call the gas supplier or a registered gas fitter ASAP.

All domestic gas has a tracer added so you can smell leaks. The tracer is usually hydrogen sulfide (H2S), ethyl mercaptan (C2H5SH), or some other noxious sulfur compound to which the human nose is acutely sensitive. The trouble is that you can get acclimatised to them, or mask them with fragrances and deodorisers, but you really shouldn't because (a) they are themselves poisonous and (b) they are there to warn you of a potentially explosive or suffocating atmosphere.

Fortunately, however much you desensitise your nose, most sulfur compounds (including egg yolk!) will eventually tarnish silver, so you have been warned. Open all the windows and call the gas emergency line - NOW.

Offline Chimonger

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Re: What causes silver to turn black in my home?
« Reply #3 on: 18/02/2016 18:38:10 »
We used to live in a rural area, where air was pretty clean.  Silver items stayed shiny much longer [weeks to months], before needing polished.  The nature of that tarnish was fairly light, and easily remedied using simple things like Bon Ami or classic Crest toothpaste.
Not anymore.  We moved. 
The new area, unfortunately, is next to an open-pit form of commercial composting farm operation. Tanker loads of chicken manure are dumped into a cesspit, mixed with straw, and allowed to compost.  [yeah, extremely nasty][and yeah, the neighborhood is starting to get a bit more cohesive to try to solve this issue...the County is the real culprit, for permitting dense development within a 1/2 to 1 mile radius of that farm with any open cesspit, and not requiring disclosure no notification to buyers, nor any monitoring of air quality incidents; also guilty are realtors who commonly hide information about this sort of property liability.]
KEY: That effluent air from the composting manure, emits methane and sulfur.
Methane is a lighter than air gas which is flammable, but doesn't do much to tarnish.  But the sulfur sure does; it is heavier than air, so sticks closer to the ground.  It infiltrates into the houses and other buildings within about the 1-mile radius of the operation.  Therefore, it is commonly ambient in the air, even when levels are low enough to not consciously smell the nasty odor. 
Both of those gasses, but mostly the sulfur, displace breathable air, and can cause burning, tearing eyes, and difficulty breathing, especially for those with asthma and other respiratory ills, if it gets to dense enough concentration for a long enough time.
Sulfur sources can be from living near heavily vehicle traffic, downwind from refineries and various chemical companies.  Sulfur can come from seeping sewer gasses from drains, Natural Gas leaking, as well as from trash dumps where things are rotting down.  Some regional water is very sulfurous [smells like rotten eggs] 
Sulfur can be in various forms. 
Some fundamental sulfur is a major component of building strong bodies..healthy.  But when it combines with other elements to make Sulfur Dioxide, or Hydrogen Sulfide gasses, for instance, that it becomes a problem.
....And here, our silver items now tarnish at very fast rates; usually within a few days; the nature of the tarnish is a far blacker, seems thicker, and definitely harder to remove.
Thinking I need to graduate to using the aluminum foil + dish soap + hot water. Unless anyone here has better cost-effective ways to achieve it, then store them in an air-sealed box, and use silver cloth to keep items wrapped in. 
What simple home remedy counteracts sulfur? 
Zinc or silver particles embedded into a felt-like fabric [silver cloth--it's usually good for about 20 years before needing replaced....unless like us, you are in a high-sulfur area], and air-absorbers to decrease humidity in the storage box.  Also using activated charcoal, is good, to help absorb airborne chemicals that can damage silver.
Things to AVOID when storing silver: 
Newspaper and rubber bands should be avoided because they contain sulfur compounds. Plastic food wrap contains chemicals that can damage silver and over time may adhere so tightly that you’d need strong solvents to remove it.   Lastly, ordinary cardboard boxes contain acids that aggressively attack silver.   Some, if not all, wood contains sulfur as part of it's structure, just as our bodies also contain sulfur.
Only acid-free archival boxes should be used to store silverware. 
Silica gel is widely available in small canisters that turn color when saturated with moisture; baking the canisters in an oven drives out the moisture so they can be reused.
Activated charcoal is the active ingredient in commercial anti-tarnish strips.


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Re: What causes silver to turn black in my home?
« Reply #3 on: 18/02/2016 18:38:10 »


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