About 230,000 Iowans, roughly 7 percent of the state, get their drinking water from private wells instead of a municipal system, according to Iowa State University Extension. A good share of those wells carry hydrogen sulfide, the gas behind the rotten-egg smell that shows up in a lot of rural North Iowa bathrooms.
The Minnesota Department of Health lists black stains on silverware as one of the everyday signs that hydrogen sulfide is in the water. The same reaction happens to a silver chain, except it happens on your neck, in the shower, every morning.
Tarnish is the visible problem. The expensive problem is a different one, and it only shows up on chains that were never solid silver to begin with.
What tarnish actually is?
Silver reacts with sulfur compounds in the air and water, mostly hydrogen sulfide and carbonyl sulfide, and the reaction leaves silver sulfide sitting on the surface. That film is what you see. It goes yellow at first, then black if you leave it long enough. Conservation research from the 1960s onward found that humidity speeds the whole thing up, which is why a chain stored in a bathroom fares worse than one stored in a bedroom drawer.
On solid sterling silver chains, that film is a few molecules deep. Twenty seconds with a polishing cloth removes it and you are back to bright metal, and you can repeat that for thirty years without meaningfully thinning the chain.
On a plated chain, polishing removes the plating. Once the coating is gone at the clasp and along the high points of each link, there is nothing to bring back. The base metal underneath is usually brass. It goes green or grey against skin.
What 925 legally means, and what “silver plated” does not
The Federal Trade Commission’s Jewelry Guides, 16 CFR 23.5, are specific about the word. A seller cannot describe or stamp a product as “solid silver,” “Sterling Silver,” “Sterling,” or “Ster.” unless it is at least 925 parts per thousand pure silver. Coin silver has to hit 900. Anything labeled with a bare “silver” needs a fineness number sitting right next to it, in the same size type.
Plating gets a much softer rule. The coating only has to be “of reasonable durability.” There is no minimum thickness in the guides, no micron figure, nothing a buyer can check.
That gap is the whole story of cheap men’s jewelry. A $40 chain sold as silver plated can be a brass core with a coating you would measure in fractions of a micron, and the listing is perfectly legal as long as it says plated somewhere. Nobody is lying. You are just buying a coat of paint.
My honest read after watching enough of these come apart: for a chain worn daily, against skin, under a collar, plating is a waste of money at any price. It is not a cheaper version of the real thing. It is a different product with a service life measured in months.
Four things to check before you pay
Look for the 925 stamp. It sits on the clasp or on a small tag soldered next to it. If a seller cannot tell you where the stamp is, that answers the question.
Look for a second mark on an Italian chain. Italy has required this since Legge 46 of 1968 and D.P.R. 1496 of 1970. Every registered maker gets a numbered polygonal mark. It carries a star next to the two-letter code for the maker’s home province, and the 925 is stamped separately inside an oval. AR is Arezzo and VI is Vicenza, the two Italian towns that most machine-made chains are manufactured in.
Pick it up. Solid sterling has real heft for its size. A 4mm chain that feels like nothing in your hand is either hollow or plated.
Bring a magnet. Silver is not magnetic. If the chain pulls toward a fridge magnet, there is steel inside it.
The repair question nobody asks in the store
Chains break. A clasp catches on a jacket zipper, a link opens up, and suddenly the thing is in two pieces on the bathroom counter.
A solid sterling chain is a bench job for any jeweler with a torch. Solid 925 solders cleanly to itself. On most link styles you cannot find the joint afterward. Call a shop in Mason City or Clear Lake before you write a broken chain off, because a single link repair is usually priced as bench minimum.
A plated chain is usually in decline. Heat burns through the coating around the joint and leaves a visible base-metal ring, so the honest shops will tell you it is not worth doing. The hollow chain has the same problem for a different reason, since there is not enough metal in the wall of the link to take solder without collapsing. That is worth pricing in before you compare a $40 chain to a $300 one, because one of them has a second life and the other has a bin.
Getting the width and length right
Length first, because it is the mistake people make. A 20-inch chain sits at or just below the collarbone on most men and stays visible above a crew neck. A 22-inch lands a few inches lower and works better under a shirt with the top button open. A 24-inch sits mid-chest and reads as a deliberate statement. If your neck measures over about 16 inches, size up one increment from whatever you were picturing.
Width is where taste and use case meet. Anything in the 1.6mm to 2.6mm range, typically a round box link, is a pendant chain. It is thin enough to pass through most bails and thin enough to vanish under a work shirt. The 3mm to 4mm band is the daily driver, and it covers most Franco, rope and wheat chains along with the narrower Cuban links. Once you get past 6mm you have stopped buying a chain and started buying a piece of hardware, which is fine, but wear it on purpose.
Price tracks silver weight far more than it tracks branding. As a reference point, MCKER’s sterling silver chains run from around $192 for a 1.6mm round box up to $958 for an 8mm Cuban, all of it solid 925 made in Italy, and almost the entire spread between those two numbers is grams of metal.
Care that survives an Iowa winter
Chlorine is the one non-negotiable. Pool and hot tub water attacks the copper that makes up the other 7.5 percent of the alloy, and the damage goes into the structure of the metal instead of sitting on top of it. Take the chain off before you get in. Chlorine exposure over a couple of seasons is what turns a chain brittle enough to snap at a link.
If your water smells of eggs, rinse the chain in clean water after a shower and dry it with a soft cloth. Two minutes, no product needed.
Store it dry and sealed. A zip bag with an anti-tarnish strip in a bedroom drawer costs almost nothing and does more than any polish. A chain that spends February in a bathroom, cycling through steam twice a day, will tarnish several times faster than the same chain in a dresser.
Skip the liquid dip cleaners. They pull tarnish off fast, and they also pull off any intentional oxidized detail in the links, which is what gives a Cuban or a rope chain its depth. They tend to leave the surface more reactive than it started. A cloth is slower and better.
One last thing worth doing on the day the box arrives. Find the stamp and check the clasp action before the packaging goes in the recycling, because that is when a return is easy and six weeks later it is not.