An allergy is a hypersensitivity to a substance that causes the body to
react to any contact with that substance.
Do I have an allergy to gold?
Probably not, that is not gold itself.
What people occasionally have is an allergy to the nickel content in
gold alloys, usually in the alloy rich 9ct golds. 9ct alloys go dull
or even black from the exposure to chemicals in the atmosphere and also
may discolour from contact with perspiration, bleach, household chemicals
and some fabrics.
Detergents and other chemicals lodge between rings and the skin causing problems,
particularly hairspray, beauty and cleaning products. Antiperspirants exacerbate
metal allergy problems. It has been suggested that the sweat of a healthy person
after exercise contains 18 times the nickel content of blood. The antiperspirant
reduces the bodies natural way of eliminating heavy metals and can lead to a
build up in intensity, which causes a higher concentration in the sweat than
is normal.
The most common type of allergy we encounter is a phantom allergy, caused by
a noticeable desire to upgrade to 18ct or platinum!. As nickel and zinc are not
used in 18ct alloy, just silver and copper, it is less likely to produce any
kind of allergy related problems. What a good excuse!
Tarnishing of Gold
Possible causes include:
- Perspiration (everyone's body chemistry is different, hence this
is why some are more susceptible than others); for women, the time
of the month can influence their body chemistry.
- Perfume, hair or deodorant sprays,
- Tarnishing during storage (storage boxes may contain organic sulphur
compounds),
- Leaching of acid/ cleaning solutions from surface microporosity from
cast jewellery; this causes corrosion locally (such porosity may even
trap perspiration during wear, causing local corrosion)
- Preparation of vegetables such as onions and spices (many foodstuffs
contain sulphur compounds and others are also acidic).
Another possible mechanism may be surface micro-porosity on the surface
of investment (lost wax) cast items. This porosity may trap acids and other
cleaning solutions, sprays, or perspiration and cause a local corrosion which
'creeps' over the surface of the item.
The tarnish films formed are generally harmless although unsightly and
may lead to a black smudging of the skin. Such films can be easily
polished off by a jeweller to restore the bright gold colour.
Possible solutions to the problem include:
- Store jewellery in a pouch or bag in a dry atmosphere (unpolluted,
e.g. by exhaust fumes, solvent vapours, where possible).
- If stored in a box or pouch or plastic bag, ensure it is free of
sulphur-containing compounds (from solvents, fabric treatments, adhesives,
etc.).
- Polish jewellery regularly with a soft cloth to remove any early
tarnish films, perspiration and other contaminants (sprays, etc). Clean
after wear and do not put on perfume, deodorants, sprays, etc whilst
wearing the jewellery
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