emerald care

I have purchased a cabochon emerald and understand that they need to be
oiled periodically.Can anyone expand on this and tell me what kind of oil I
need to use.
est.x

Yes. Oil of citron.
And don't put an emerald in a ultrasonic cleaner (it lose the treatment).

Marco




"Esther Pilcher" ha scritto nel messaggio
...
I have purchased a cabochon emerald and understand that they need to be
oiled periodically.Can anyone expand on this and tell me what kind of oil
I
need to use.
est.x

On Fri, 05 Mar 2004 07:35:29 -0800, in rec.crafts.jewelry "Esther Pilcher"
wrote:

I have purchased a cabochon emerald and understand that they need to be
oiled periodically.Can anyone expand on this and tell me what kind of oil I
need to use.
est.x


Emeralds do not need to be periodically oiled, though for a cabochon cut, you
won't be harming it (or helping it).

Emerald is one of those types of stone which usually forms with LOTS of
inclusions, meaning both inclusions of other minerals and materials, but also
cracks and fissures, which can be partially healed, or open to the surface.
This means that many emerald look rather cloudy and "flawed". This is
especially true of the lower clarity grades, which are what are usually used to
cut cabochon stones. Better ones are usually facetted, though one can find
fine cabochons too, if one wishes.

Anyway, it's long been known and practiced that certain treatments can take
stones like this, (not just emeralds), and fill any of these fractures or
fissures that reach the surface, with a material that makes them a LOT less
visible, thus making the stone appear cleaner and brighter. Most of the time,
with emeralds, this means one or another type of oil, though in recent years,
there are also some other materials (epoxy based resins in particular) which
have proven useful. So unless you buy an emerald which is specifically stated
to not have been treated or oiled, it's safe to assume that it was oiled in
this manner, to fill surface reaching fractures, long before it was made into
your jewelry. Often, the stones are treated while still rough and uncut, and
other times, they are treated after cutting, but in the end, the majority of
emeralds on the market have been treated, and this is usually referred to as
having been oiled, even when the actual material may have been something else.

Normally, with proper care and only gentle cleaning, the oiling is fairly
permanent, and most customers will never notice any degredation in the
appearance of their stones, even after years of wear, at least not due to
drying of the oil or it's removal.

So for you to add more oil will not generally do anything. oiling or fracture
filling will only affect those fissure and breaks which make it to the surface
of the stone, since none of these materials can actually penetrate solid
emerald. Most of the types of breaks and fissures that CAN be filled are very
tiny and thin, and it usually takes more than just dipping or brushing to get
the oil to penetrate these things. Commonly, some combination of gentle
heating, vacuuming (to remove any air in the fissures that may already be
there) and sometimes pressure, to force the oil in, are used, and as I've said,
once done, it's usually pretty premanent.

But as another poster has also mentioned, you CAN damage the oiling with
cleaning methods that are too aggressive. Some very strong cleaning agents, or
solvents, can remove some of the oil closest to the surface, and ultrasonic
cleaners in particular, can also remove the fracture filling materials in some
stones. So rather than worrying about oiling your stone, it's more important
to just be gentle in how you treat it and clean it. That will do a lot more to
give the stone a long life than any oiling you might give it. If the ring
needs cleaning, stick to gentle detergents like dishwashing soap or things like
that, and don't let the ring soak in such things for long periods of time. If
in doubt, let a professional clean it, though if you're unsure about the
experience level of the jeweler it might be prudent to ask that they not use
the ultrasonic cleaner. (as with any profession, everyone was a beginner
once, and this includes jewelers. And in many stores, it may be a sales
person, not a trained jeweler, who does the cleaning, and some of them don't
realize the proper care needed with emeralds. Now, in a practical world, most
of us still use ultrasonics with most emeralds. But we're cautious with them,
and usually only put the ring in briefly, long enough to just loosen the dirt
and grime, instead of putting the ring in and coming back in a half hour
knowing that by then it must surely be clean... This latter is not a good
idea with most emeralds (and a number of other stones that can be sensative to
such cleaning).

Anyway, after all that typing, the short answer is, again, you don't need to
oil your emeralds. If it would help it, it's already been done long before you
got it, and your additional oiling will only make your ring oily.

Cheers

Peter Rowe

graduate gemologist, goldsmith, etc,
and someone who's made enough of the mistakes and messed up
enough emeralds over the last 30 years (hey, not all THAT many, now...)
to have a pretty good idea by now how to treat emeralds... :-)

thanks for that information...very interesting!
"Esther Pilcher" wrote in message
...
I have purchased a cabochon emerald and understand that they need to be
oiled periodically.Can anyone expand on this and tell me what kind of oil
I
need to use.
est.x