Do eelskin wallets demagnetize bank teller cards?

Dear Cecil:

I hope you'll be able to solve the mystery behind eelskin wallets and their supposed ability to demagnetize my automatic bank teller card, rendering it completely useless. After going through four new plastic cards in as many weeks, I complained to the bank and was told that I was either (1) exposing them to excessive heat, water, or microwaves; (2) scratching them; or (3) keeping them in an eelskin purse or wallet. When I answered affirmatively about the eelskin, I was told it's demagnetizing the black strip on the back of the card. When I asked how eelskin could do this, the only response was, we don't know, it just happens. I have asked others with eelskin wallets and they've been told similar tales. What goes on?

Cecil replies:

Cecil has been working his little heart out on this for six months now, and though he does not have the final answer, he thought it wise to give an interim report so as to avert national panic. I have checked with my banker friends (believe me, the success of the Straight Dope books has elevated me to a whole new social stratum), and they confirm that stories about eelskin wallets are widespread in the industry. No doubt this is in large part because of press reports. Actual evidence, however, is skimpy and anecdotal.

Numerous explanations for the phenomenon have been offered. Some say the creatures used to make the wallets are electric eels, and that sufficient electric charge survives the tanning and manufacturing process to sabotage teller cards. Others say that an iron compound is used during tanning that remains in the leather and is capable of retaining a charge, possibly produced by static electricity resulting from friction in, say, a hip pocket.

A variation on the preceding is that the wallets pick up a charge during shipping. It’s known that a ship traveling through water generate its own magnetic field. Some speculate that during the long sea voyage from factories in the Far East this field leaves an electrical imprint on the ship’s eelskin cargo.

This simplest explanation, however, which Cecil must say he greatly favors, is that many eelskin wallets have magnetic clasps. Since eelskin is thinner than cowhide, the magnet comes in closer contact with the wallet’s contents, conceivably to the point that it might demagnetize a teller card.

Obviously this was another job for the Straight Dope Science Advisory Board, financial division. We called up our buddy Henry, a banker of experience and breeding. He advised us that he had purchased two eelskin wallets during a recent junket to the Virgin Islands, one with, one without magnetic clasp. Entering immediately into the spirit of things, he crammed them full of teller cards and placed them in a “magnetically neutral environment” (Henry loves this scientific crap), which turned out to be the top of his bedroom bureau. Fifteen days later he tested the cards. All worked perfectly.

Next, Mrs. Adams bought me a two eelskin wallets of my own. Retail value: $22, completely bankrupting the Straight Dope Research & Entertainment Fund. (Donations gratefully accepted.) The wallets were dyed a hideous red. Forget the eelskin, I exclaimed, the color alone will demagnetize the cards! I loaded the wallets with cards and stashed them in strategic locales on my person, then went about my daily routine, testing the cards every few days. No dice. It got to the point that the magnetic clasp on one wallet made a noticeable dent on the black strip on the back of one of the cards — but it still worked.

Meanwhile, a worried manager for a major wallet-making concern called to see how things were progressing. (No kidding.) I comforted him as best I could. A woman told me that when she bought an eelskin wallet her teller cards stopped getting demagnetized — obviously a case of deep and troubled vibes.

But I personally couldn’t get the cards to do doodly. I despaired. Then help came from an unexpected quarter — the daily newspapers. I read that the famous eelskin wallet controversy had been solved. Unfortunately the papers managed to omit such details as what the solution was. To determine the facts I called up Katie Jarman, the assistant vice president at the Bank of America in San Francisco who was credited with solving the mystery. To my delight, I discovered that Katie, in the great tradition of Straight Dope Home Science, had undertaken an experimental regimen that would have done this column proud.

After a sudden rash of complaints about bad cards from eelskin-wallet owners, Katie and her colleagues examined the magnetic stripe on several failed cards and found that magnetic information had in fact been erased. They further noted that most of the complainers were women who used eelskin wallets with large magnetic clasps. As an experiment, Katie ran a variety of magnetic items over some test cards. Sometimes the cards became demagnetized, sometimes not. But when she ran an eelskin-wallet clasp over the cards, they always became demagnetized, even at a distance of two inches. A call to the fellow who owned the patent on the special donut-shaped magnet used on eelskin wallets confirmed that the magnet was unusually strong. (Why you need a heavy-duty magnet on an eelskin wallet is not clear to me, but hey, not my problem.)

Katie and company then ran a variety of eelskin products that didn’t have magnetic clasps over the test cards. (Her boss, a sucker for kitsch, had picked up a boatload of souvenirs during a trip to Korea.) All the cards continued to operate normally. Conclusion: it was the clasp, not the eelskin itself, that did the demagnetizing. (The eel in question, by the way, is the hagfish, not an electric eel.) The Bank of America began advising its customers to keep their teller cards in a separate place to avoid demagnetization.

Meanwhile, eelskin-wallet makers scrambled to save their hides, so to speak. Katie said at least one company had come out with a polyester clasp. But for some it was too late. Two companies reportedly had already gone belly up. A slimy business, if you ask me. I think the whole thing stinks.

Department of inidispensable clarifications

Dear Cecil:

Far be it from me to question you, but in your discussion of eelskin wallets, you mentioned that the “eelskin” in question was actually the skin of the hagfish. Hagfish are agnathans, or jawless fishes, and thus barely related to eels at all. I’ve had the “honor” of having to care for live hagfish for a zoology class. If you’ve ever seen one you know it exudes gobs and gobs of disgusting mucus and can turn a whole tank full of water into a tank full of slime in minutes. What I would like to know is (a) how come the companies call them “eelskin” wallets instead of “hagfish” wallets, and (b) what do they do with all that slime?

Why do people feel compelled to tell me things like this? My feeling is, if it’s long, squirmy, and unconnected to a higher vertebrate, it’s an eel. As for the wallet companies’ choice of terminology — listen, would you want to be called a “hagfish”?

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