The wife loses a stone; the husband blames the wife; the wife blames the jeweler; the jeweler blames the manufacturer; the manufacturer looks for an answer. Hoover & Strong answers the question. What causes most prong breakage? Chlorine and bromine. Where does it come from? Hot tubs, swimming pools and laundry products. Hoover & Strong has conducted a controlled experiment to determine the effect of common chlorine and bromine products on jewelry settings. We tested household bleach, (heated and unheated), hot tub chlorine and bromine solutions, and a chlorine free dishwashing detergent. We tested 14K and 18K nickel white settings; set and unset, rhodium plated and not plated; palladium white gold and platinum settings.
Hoover & Strong’s testing rates their products from the most durable to the least durable as follows: Platinum; rhodium plated 14K palladium white gold, 14K palladium white gold; rhodium plated nickel white gold, 18K nickel white gold; and 14K nickel white gold.
Chlorine and bromine are commonly used chemical products to prevent bacteria from growing in our drinking water, in swimming pools and hot tubs. Too much of these compounds added may cause a human health threat and a durability problem for settings. The higher the concentration, the longer the exposure and the higher the temperature, the faster the deterioration of the settings.
Stress occurs in metals when they are worked. Stress can be relieved in metals by proper heat treating. A simple experiment to demonstrate this can be performed by bending a paper clip until It breaks off, count the number of times you bend the paper clip. Next bend the same paper clip just short of its breaking point. Heat the paper clip to a cherry red and let it cool. This IS called annealing. Now bend the paper clip and count the number of times you have to bend it before it breaks. The annealing relieved the paper clip stress.
The test solutions are listed in order from the product causing the most damage to the least harmful.
The rings soaked in heated bleach suffered the most catastrophic failure. The 14K nickel white gold was the first to fail in all solutions except the household detergent. The household detergent had little or no effect on the rings or settings. The test was stopped when the first setting failed and all items were compared.
Based on our testing, a consumer wearing a 14K nickel white gold setting would lose a stone or expect prong breakage as follows:
Results Of Each Solution
- 5% chlorine bleach heated to 110°F, prong failure would occur after 21 hours of exposure. Only the platinum and palladium white gold settings held their stones in the worst test solution.
- 5% chlorine bleach room temperature -prong failure would occur after 120 hours of exposure.
- 5 ppm (parts per million) chlorine using hot tub chemicals-prong failure would occur after 312 hours or 156 days.*
- 5 ppm (parts per million) bromine using hot tub chemicals-prong failure would occur after 384 hours or 192 days. *
- Household detergent -no visible effects on the setting.
* based on 2 hours a day, 7 days a week
Hoover & Strong’s recommendations: Use platinum settings, 14K palladium white settings. Rhodium plate 18K or 14K white settings, the rhodium plating will provide a protective coating to protect the setting; similar to paint stopping rust.
Last but not least, tell your customers not to wear their jewelry in hot tubs and swimming pools. Take jewelry off when using laundry or cleaning products. NEVER, NEVER clean rings with bleach. Suggest that they bring them to you for cleaning and a checkup, just like going to the dentist to have their teeth cleaned and checked.
Copyright® 1998 Hoover & Strong