reaction between gold and mercury ?
ire...@ac.dal.ca
A friend of mine broke a thermometer and had some mercury spill onto her
14 carat gold ring. After a short period of time some of the surface of the
ring turned a silver color and was slippery to the touch. The color of
the ring is slowly returning to normal now. Has the mercury reacted with
the gold in the ring? Is it reversible? I remember hearing that mercury
is used in the mining of gold in the Amazon and is contaminating rivers.
I would appreciate an explanation of the reaction between gold and mercury
and whether the ring has suffered permanent damage. Thanks.
Keith Conover
ire...@ac.dal.ca
Karri Tapani Palovuori
Incredible! I recently red a chimistry book that described a treatment
for this exact accident. It was interesting, but I never figured that it
could be usefull as well.
This is what you could do:
(And remember, this supposes that there's no stone in the ring)
1) Heat the ring red hot (but do not melt it) with a bunsen in a hood.
The mercury distills off.
2) Let the ring cool. DON'T PANIC. It is now black because of the copper
that has oxidiced on the surface. 14 carat gold typically contains
10/24 copper.
3) Wash the ring with diluted hydrochloric acid. The ring turns golden
again.
4) WASH THE RING WITH WATER before using it. ;-)
>Keith Conover
>ire...@ac.dal.ca
Karri
P.S. If there were any miscoloration in the ring after this treatment, you
could repeat steps 3 and 4 using diluted nitric acid. Remember to wash
the ring _before_ and _after_ the nitric acid. If there were still
miscoloration (highly unlikely) you could polish the ring with some
ring polishing agent. Naturally - you could do this anyway. :-)
Brent Besler
The gold dissolves in the mercury in much the same way salt dissolves
in water. The mercury probably removed a small amount of gold from the
surface of the ring.
SYG
>>the ring is slowly returning to normal now. Has the mercury reacted with
It formed an amalgam.
(Electrochemists do this all the time....with gold electrodes that is :-)
(You can tell a careless electrochemist from the silver spots on their
gold rings :-))
>1) Heat the ring red hot (but do not melt it) with a bunsen in a hood.
No need to heat that hot. warming the ring willwork, as well, but
do it in the open (or in a hood)
Do not wear the ring until the mercury is removed...
Michael Whitbeck
* A friend of mine broke a thermometer and had some mercury spill onto her
* 14 carat gold ring. After a short period of time some of the surface of the
* ring turned a silver color and was slippery to the touch. The color of
* the ring is slowly returning to normal now. Has the mercury reacted with
* the gold in the ring? Is it reversible? I remember hearing that mercury
* is used in the mining of gold in the Amazon and is contaminating rivers.
* I would appreciate an explanation of the reaction between gold and mercury
* and whether the ring has suffered permanent damage. Thanks.
*
* Keith Conover
* ire...@ac.dal.ca
A Au-Hg amalgram is made. Considering the toxicity of Hg I
wouldn't wear that ring. Maybe a jewler can fire it to drive out
the mercury (don't do this at home Hg vapor is BAD NEWS).
~=+
Roy Smith
> Heat the ring red hot (but do not melt it) with a bunsen in a hood.
Then, darken the room, and remove the ring from the fire. Hold the
ring up to your eye (no need for tongs or gloves, it should be quite cool)
and see if you can read any flowing script writing inside which was not
visible before (don't worry if you can't understand the language). If you
do see writing, consult your local wizard and/or elven council for proper
disposal techniques. :-)
--
Roy Smith, Public Health Research Institute
455 First Avenue, New York, NY 10016
r...@alanine.phri.nyu.edu -OR- {att,cmcl2,rutgers,hombre}!phri!roy
"Arcane? Did you say arcane? It wouldn't be Unix if it wasn't arcane!"