When we were in Las Vegas (attending trade shows) a couple of weeks ago part of our mission was to find hypoallergenic earring posts and a relatively inexpensive hypoallergenic clasp for a pearl bracelet. The search proved harder than it first appeared to be. In large measure this probably stems from the fact that the metals used in jewelry are largely hypoallergenic. This doesn’t mean that they are absolutely hypoallergenic; in the absence of any U.S. Government standards for the term, the expression ‘hypoallergenic’ has come to rest on a broad understanding that a metal called hypoallergenic is not likely to cause an allergic reaction. In other words, most people will not be allergic to it, but some may. Spare your indignation if you believe you suffer from a metal allergy and read on.
In my experience, most people who complain of metal allergies have, in fact, reacted to soap built up on earrings or inside rings or chains. If you are not up on your chemistry, allow me to explain how this may be so. Virtually all soaps are alkalis; that is, they are soluble bases. They clean your skin by attacking it, literally ‘burning off’ the top layer. If you find this hard to believe, just look at a classic formula for ‘castile soap’; it’s primary ingredients are olive oil and sodium carbonate, a powerful caustic. In fact, taxidermists use sodium carbonate added to boiling water to remove flesh from the skull or bones of an animal to create an educational display. On a smaller scale, water or perspiration can activate the soap film on a piece of jewelry into a flesh eating demon. So if you think you have a metal allergy, the first thing to do is to eliminate soap from the equation; that is, have the jewelry you are suspicious of professionally cleaned of all soap residue. Once soap has been eliminated you can look for a classic indicator for a metal allergy, corrosion.
Green corrosion on a piece of jewelry, usually sterling silver, is almost always indicative of a reaction to nickel. Nickel shows such significant chemical activity as to be an allergen for many people; but interestingly enough its presence on silver jewelry rests on this chemical activity. The common silver alloy, sterling silver, is 92.5% silver and 7.5% copper; and when it is exposed to sulfur (a very common part of industrial air pollution) it discolors. To prevent this, it has become fairly common for many jewelry makers to rhodium plate their sterling silver production. Rhodium, a very ‘white’ member of the platinum family of metals, is hypoallergenic - and very expensive. To complicate using it further, its relatively inert character makes it difficult to get a good rhodium plate on silver. Enter nickel. Owing to its chemical activity, it is easy to apply a very thin and smooth nickel plate over silver; but both its activity and its off white color make it unattractive to leave it at this. Fortunately, nickel loves rhodium; so the next step in production is to plate the piece with rhodium thus giving it a beautiful silvery finish that will not discolor. However the rhodium plate is only a few thousands of an inch thick; so a scratch through it will expose skin to nickel and create the possibility of an allergic reaction.
Between soap and nickel, this accounts for most presumed jewelry allergies; this brings me back to our search for earring posts and a pearl clasp. Both clients have proven allergies to nickel, either in its ‘raw’ form or when alloyed with gold; unfortunately nickel is the common whitening agent in white gold alloy. Since there were some real price constraints on the posts, we sought palladium posts (palladium is another, less costly, hypoallergenic member of the platinum family); but couldn’t find any. We had to rethink the problem. The customer wanted Tahitian black pearl earrings; so we decided to shop the pearls first. If we could buy nice pearls reasonably enough, we could have the earrings made with platinum (hypoallergenic) posts. With careful shopping we succeeded. Interestingly enough, the pearl bracelet clasp posed a greater problem. Again we were up against price constraints The woman needs a white metal clasp that is free of nickel. This eliminated white gold alloys and most commercially available sterling silver. Platinum was available, but it exceeded her budget. So we wandered the Las Vegas Jewelry Show looking for raw (unplated) silver; and it was harder to find than we had imagined. Finally we were able to make a connection with a manufacturer who, at relatively reasonable prices, was willing to sell us a sterling silver ‘semi-finished’ clasp - ‘semi-finished’ meaning unpolished and unplated. With a sense of relief, we went on with the rest of our business.
If you’ve not noticed, there is more than one point to this story. The first is that complaints about jewelry metals must be carefully considered to see if they are valid. The second is that we take our clients’ needs very seriously. So if you’re in the market for a superb piece of jewelry, you really need to come see us. We hand select our diamonds for exceptional beauty and we demand the very best in jewelry manufacture - including the many custom pieces we make each month. Check out our website for a sense of our style (http://www.hurstsberwynjewelers.com/); then phone us at 708.788.0880 for an appointment to select or design the ring, necklace or earrings of your dreams. We’re Hursts’ Berwyn Jewelers, not a common jeweler.
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