I have a system of finishing that I am really happy with. Fabricate,
file, pumice, pre-polish, polish, ultrasonic (to clean off polish),
stone setting, clean-up and re-polish (where necessary), clean with
ultrasonic, rinse. The use of the ultrasonic with soapy, ammoniated
water works really well, completely cleaning off any remaining
polish residue and leaving the jewellery lovely and shiny.
My question is that whilst this method works well for stones that
will stand up to the the use of the ultrasonic, what do other people
do to achieve that final clean-up after stone setting with stones not
suited to the ultrasonic? I have not found another way to
successfully remove the polish residue and still leave the jewellery
in its finished, shiny state. Also, if I was to use the ultrasonic
cleaner on something like a tanzanite, emerald or peridot, etc, what
effect would it have on the stone? I have put quite an expensive
peridot through the ultrasonic and am wondering whether I may have
done some microscopic damage to it.
Brad Simon, publisher of -Bench newsletter and Bench magazine is a
frequent contributor here. A series of articles authored by me called
“Colored Gemstones at the Bench” have been featured in both the
newsletter (abbreviated form) and the magazine. These articles
address some of the characteristics of common gemstones and how they
should be handled at the bench. Brad’s newsletter is free to all who
request it at http://www.bwsimon.com/e-bench/ and I receive no money
for my articles.
To more directly answer your question:
Tanzanite should NEVER be placed in an ultrasonic cleaner. It MIGHT
survive, but I have seen ten carat plus stones instantly and
completely destroyed. Tanzanite is soft, brittle and very sensitive
to thermal shock, I.e., sudden temperature change. Placing a stone
into hot pickle is a questionable practice, and extended stays in the
pickle can adversely affect the surface of a polished Tanzanite,
depending on the composition of the pickle.
In and of itself, emerald is very hard and quite durable.
Unfortunately. most of the emerald that comes across the bench has
been treated, and sometimes that treatment hides the many small
fractures that may be present. Those fractures are planes/areas of
weakness in the crystal, and sudden changes in temperature or a
little too much pressure from a setting tool, and, “POOF!”. This has
led many to think emerald is not hard or durable, but “clean”
emerald presents little problems in handling. But, you may never run
a cross one.
Peridot does not seem to suffer from thermal shock or the vibration
of an ultrasonic, but most pickling soultons will quite rapidly etch
the surface, calling for a complete re-polish or re-cut of the
stone. Repalcing a 1-2 carat peridot will not break the bank,
but…if you have not checked the prices of peridot in the four
caratand uprange lately, you may be in a for a real shocker. For
good Pakistani material over 5 carats, expect to pay at least $150/c
and for stones 7c plus, much more. After Tucson, we will all be
seeing the results of the weak dollar in colored gems and many US
jewelers will definitely have sticker shock. So keep the peridot
away from the pickle!
Soap and water with a soft toothbrush cleans everything!
An alternative you may contemplate are flexshaft mounted 3M bristle
brushes, I frequently employ the light green 1 micron grade to clean
up combination enameled/ stone settings where the geometry of the
piece does’nt lend itself to other finishing techniques.
It can be a comparatively slow process compared to other techniques
but does provide an immaculate mirror finish with no residue
problems.
I prefer to have a piece all “ready to go” before setting a stone in
it, therefore no worry about whether it can go into the ultrasonic.
It’s already as shiny as it will be, then I carefully set the stone
(sometimes using masking tape to protect metal areas next to the
bezel). Now, slip-ups do happen, and then perhaps a little touching
up could be necessary, but I suppose if that was an issue, and it
was a stone that couldn’t go into the ultrasonic, I’d do my best
without it.
By the way, you have certainly been working hard at your bench all
of these months, I’ve really been impressed with your vigor, when
will we get to see some of your latest creations?
I prefer to have a piece all "ready to go" before setting a stone
in it, therefore no worry about whether it can go into the
ultrasonic.
I like to do the same, but sadly my stone setting skills leave a lot
to be desired and I often have some clean up to do to get rid of
tool marks. I’ve taken to using more substantial silver for bezels,
which I can’t turn over by hand and bezel pusher so I need the help
of a hammer which I use with a prong pusher that I’ve polished the
end of (so that it leaves minimal marks).
y the way, you have certainly been working hard at your bench all
of these months, I've really been impressed with your vigor, when
will we get to see some of your latest creations? :-)
Wow, thanks. Well I’m hoping that my husband will take lots of photos
for me within the next week. I’ve been making loads of things as
Christmas presents and I want them documented by photograph before I
post them out to family members so I’ll let you know, hopefully in
the next week or so. I’m very cross with myself today though. I’ve
been making about two or three pieces a day (to get them out for
Christmas) and I was soldering together the pieces of a pendant
today and I melted a part of it! GRRRRR!!! That puts me an hour
behind and I’ve lost some silver in the process.
Thanks so much for the recommendation of Brad’s newsletter and your
articles and also for your direct advice regarding the
I will definitely keep my peridot and tanzanites away from the
ultrasonic and pickle. I’m glad I bought my large piece of peridot
before the prices went up. I’ve noticed that they’ve soared
recently.
Regarding cleaning things which cannot go in the ultrasonic, I’ve
not had much luck with the soap and soft toothbrush. I don’t know why
but I suppose it’s probably the wrong soap and I should try another.
Peridot is usually on those lists recommending NOT to put it in the
ultrasonic. Altho I’ve had many peridots make it happily thru this
cleaning process a setter who was working for me cleaved a very large
one – in the ultrasonic. Very expensive learning process.
What about steam cleaning? While I’m debating whether to get an
ultrasonic cleaner, I have a household steamer that I occasionally
use to get polishing residue out from behind settings. Are there
stones that can’t take that?
Have you tried hot water and soap with a few drops of amonia? Hand
soap not washing up liquid as it leaves a residue and doesn’t wash
clear especially on diamonds. That’s what I use.
Helen…I mix a batch of liquid to use after the polishing…one
cup water; 1 tablespoon Palmolive liquid dish detergent (don’t use
Ivory, but Dawn is OK); and 1 tablespoon sudsy ammonia (the other
would work). Apply directly to the item with a damp soft brush
(toothbrush in my case), gently scrub. It’s OK to let the item soak
in the solution for a while. It’s a great finger cleaner also after
the black of polishing. I mix this in volume, using the formula
above. Give it a try.
Over the years i have had peridot come out of the ultrasonic all
hazy, like it was treated (oiled like emeralds). It lookes like the
ultrasonic just sucked out the treatment. Though i have not really
been able to locate any text that says peridot is treated like that.
My ultra sonic solution is the blue stuff from stuller its happened a
hand full of times. Has anyone ever heard of a peridot treatment like
that.
Regarding cleaning things which cannot go in the ultrasonic, I've
not had much luck with the soap and soft toothbrush. I don't know
why but I suppose it's probably the wrong soap and I should try
another.
i’m a long-time lurker on this wonderful forum, just returning to
the jewellery craft after many years absence. not quite sure how to
reply to a post here, so i hope this works!
i’ve just bought an u/sonic cleaner, but in the past i had perfectly
reasonable success with an electric, vibrating toothbrush (some of
them have very small brush heads) and ordinary washing up liquid
(quite strong) - i used to keep the w/up liquid in an old electric
kettle, so’s i could warm it up a bit.
Have you tried hot water and soap with a few drops of amonia?
Thanks Mary, I’ll try that. It was washing up liquid I was trying
but I’ll try the hand soap plus the addition of a few drops of
ammoniated water. Many thanks.
I am going to say something very controversial. Peridot is very
misunderstood gem due to it’s “apparent” abundance. The reason why I
use quotes around apparent will become clear in a minute.
Peridot is derived from french peridote which is the name for
chrysolite. Another name one may encounter is noble olivine.
Chrysolite is usually found in small-grained aggregates. In order to
become peridot these aggregates must undergo trans-crystallization in
presence of hydro- thermal solutions, or what is called metasomatism.
The resulting crystals are not as abundant as may seem, especially
in larger sizes. Chrysolite as aggregate is frequently found in
kimberlites, or in other words is a by-product of diamond mining.
Such aggregates can be treated as emeralds to create appearance of
peridot. Since gemological properties ( hardness, RI,…) are the
same, ignoring ethical considerations, it is called peridot.
I cannot site any official sources for this. But I was wondering
about the effect of ultrasonic on peridot for a while, and it is the
only explanation I was able to come up with.
What about steam cleaning? While I'm debating whether to get an
ultrasonic cleaner, I have a household steamer that I occasionally
use to get polishing residue out from behind settings. Are there
stones that can't take that?
I’d also be interested in the answer to your question. I suspect
(and wait to be corrected) that the stones which can’t stand up to
the ultrasonic, also may not stand up to steam cleaning?
I mix a batch of liquid to use after the polishing.....one cup
water; 1 tablespoon Palmolive liquid dish detergent (don't use
Ivory, but Dawn is OK); and 1 tablespoon sudsy ammonia
Thanks for the recipe. It’s basically the same as the solution I use
in the ultrasonic so that should be easy enough. So ammonia won’t
harm the more delicate stones?
Peridot is a bit soft. Some ultrasonics can generate a LOT of
energy. especially with a nice clean solution, all that energy is
concentrated in the expanding and collapsing cavitation bubbles that
form at any surface in the liquid. That, of course, is how the
ultrasonic does it’s effective job of cleaning. But it can be
actually fairly seriously aggresive energy, and some softer surfaces
can be damaged in some machines. Usually, it’s softer stuff than
peridot, but I’d not rule out the possiblity. It’s quite common, for
example, to see ultrasonics able to damage the polish on cast
sterling silver or other soft metals. It might also happen if there’s
more aggressive polishing compound in solution, which the ultrasonic
energy then might be turning into an abrasive action on the peridot.
Peridot is also sensative to acid. So extending immersion in things
like your pickle, or rhodium plating baths, or other acidics
solutions, WILL damage the surface. Leave a peridot in your pickle
for a while, and it won’t be just hazy. It will be decidely dull and
matte.
It’s also possible that some stones have a slight wax or oil layer
on the surface. This differs from the usual treatment of emerald,
where the aim is to penetrate and thus hide actual surface reaching
fractures and fissures. In peridot, which usually isn’t included,
there’d be no reason for that. But some polishers might leave a
little wax on the stone if they’re not getting the best polish for
some reason. That’s more common with cabochon material, but who
knows. My vote, though, would be that the energy of the ultrasonic
is actually damaging your peridot surface, not removing some
treatment. Some brands of ultrasonic are really rather violently
aggressive. They clean really fast, but in a trade off, are too much
for some materials.
One thought, useful for those instances where certain items cannot
be cleaned in an ultrasonic, is to remember that jewelers did before
we had the ultrasonics. It’s slower, but still a highly effective
method.
The boil out pot is simply an old saucepan filled with a suitable
fairly strong detergent, allowed to simmer away on a hot plate.
Jewelry items soaking in there will have their polishing compounds
nicely removed if the detergent is strong enough. TSP (real TSP, not
the fakes) is a decent grease/oil/wax cleaner, and that’s what we
use. The classic, I think, was sodium hydroxide, or lye. This makes a
really strongly alkaline cleaner. There are few things that cannot
go in there, notably organics like amber, and perhaps other resins,
and maybe some types of glued things. And I’d have reservations with
porous things like turqoise, especially if treated in any way. But
mineral based stones are generally fine. Opals, for example, are just
fine in there as are tanzanites or other stones generally not safe
for the vibrational energy of an ultrasonic. Rinse in hot water first
to warm them up, reducing heat shock, if appropriate. TSP seems fine
for treated emeralds (not oiled perhaps, but the more recent
treatments), so long as it’s not in there longer than needed. Lye,
well, that’s more aggressive, so I’d not be sure.
But in any case, a simmering (just below boil, or a low boil) pot of
a strong detergent will get the polishing compounds off of almost
anything if you give it a bit of time, and so long as it’s not
something that would chemically be attacked by your detergent, it’s
quite gentle. Your cast silver, for example, won’t loose it’s polish
like it can do in an ultrasonic…
