Back to Ganoksin | FAQ | Contact

Allergy to Magnetite?

Hi, I recently bought several pounds of Magnetite in “maybe Jade,
maybe something else”. It’s very attractive material; very dark
greenish with nice magnetite patterns.

Recently, a customer was sorting through it, picking pieces to
buy. After about 20 minutes, her fingers had turned a yellowish
orange color. Needless to say, she was nervous about buying any
after that.

So here’s my question…Have any of you ever heard of this
happening? Did she have an allergic reaction to the iron in the
magnetite? I had my hands in this rock for a couple hours while I
was sorting it, with nothing more than dirty hands as the result.
I’m planning to sell this material at the Denver Show next month,
so if I have a problem with it, I need to know what to do about

Thanks for any advice,

[paraphrase] Karen mentioned a customer’s reaction to magnetite
(stained hands), a problem she doesn’t share…

First thing that comes to my mind, Karen, is whether your
perspiration is acidic? My guess is no, and that your customer’s

I know jewelers who just cannot keep rust off their tools, no
matter how much oiling they do…same sort of thing that causes
the black reaction to gold alloys in some people, and not in
others. It’s common enough that GIA teaches it as part of the GG
and GJ programs, including methods for combatting the problem
(plate in 24K, or use clear nail polish as a temporary measure).
I’ve heard of customers trying to claim that they were sold junk
metal as a result of their reaction to certain gold alloys…

(Imagining how you’d ask that in a customer…“Excuse me, would
you mind hanging on to this litmus strip for a second?”)

Kat Tanaka

G’day, Suzy; I personally have never heard of anyone with an
allergy to magnetite, or Jade for that matter. But people do get
allergic to the strangest things. Allergies are invariably
accompanied by a rash or some sort, but you didn’t mention that.
Certain oxides, silicates hydroxides and phosphates, etc of
iron are orange-yellow to deep orange and it could be this which
discoloured your client’s hands. There are enormous quantities of
magnetite sand here in NZ, especially on the West Coast of the
North Island. So much that many of the beaches are completely
black - and painful to walk on with bare feet in summer because
the black absorbs the heat from the hot NZ sun. So much black
sand-magnetite (titano-magnetite:- iron, titanium, silica) that
we have been flogging millions of tons of beach sand to the Japs
so they can make steel with it - and sell it back to us in
cars(!!!) However, my point is that hundreds and thousands walk
about and lie around half-naked on our Taranaki black magnetite
beaches and I have never heard of anyone coming to harm - other
than getting badly sunburnt and eaten to distraction by
sandflies. But then I don’t know much, eh? Cheers,

       / \
     /  /
   /  /                                
 /  /__| \      @John_Burgess2
(______ )       

At sunny Nelson NZ in late winter/early spring with lambs, daffs, tree
blossoms, Cold starry nights, cold sunny days

Kat, it’s possible to get a customer to cooperate and let you do
a litmus test, if you’re very tactful and explain you are just
trying to help solve the mystery or problem. Try it sometime? I
did it for a jeweler when asked some years back. Wasn’t me; was
truly the inferior metal in his piece, which he then willing
replaced. Sharon Holt

    Kat, it's possible to get a customer to cooperate and let
you do a litmus test, 

G’day; Sorry, but I doubt that a litmus test will help very
much. Firstly you would have to use something a bit more
sensitive than litmus, such as one of the pH papers (sometimes
sold in gardening shop) but such a paper would have to be wetted
with a drop of neutral water - even water from a still would very
rapidly dissolve carbon dioxide from the air to give a slightly
acid solution, making the test unreliable. Next what
discolours silver and the lower carat golds is sulphides, not
just acids. Sweat contains sulphur compounds, even that of the
cleanest people. The quantity of sulphur compounds in sweat
depends upon a very large variety of factors, heredity and diet
being only two of them.

I’m afraid that people who find their jewellery staining have
four options: keep it clean; wear only high carat gold (18ct
and above); move away from the city; don’t wear any!

       / \
     /  /
   /  /                                
 /  /__| \      @John_Burgess2
(______ )       

At sunny Nelson NZ in late winter/early spring with lambs, daffs, tree
blossoms, Cold starry nights, cold sunny days Only it’s foggy right now!