Your most horrible cleaning mistakes.

As I sit here looking at a few pieces of damaged zincite which I left in HCl too long (trying to clean off something I probably shouldn't have anyway) I wonder, what is everyone's biggest cleaning mistake? Maybe you can help someone avoid making the same mistake by sharing.

The lesson I learned. Don't put Franklin specimens in HCl. At least not for long. It will erode more than calcite.

I've read about someone who was cleaning CYANOTRICHITE using hoover (-; About the HCl - I know its good for cleaning SOME Baia Mare/Baia Sprie hydrothermal minerals specimens (as my friend do).

I had this piece from an Alpine cleft I found two years ago in Austria.
It was a nice group of Quartz crystals up to about 12 cm in Chlorite.
When I removed the Chlorite it turned out that there whas a lot of "Brauneisenstein" (mix of Limonite and Carbonate) around the crystals.
In order to get the group free I put the thing in HCl (as I often do when cleaning).
When I got it out the whole thing was in to pieces, turned out that the "Brauneisenstein" was holding all together (the Iron rich carbonate apparently filled in the cracks caused by tectonic movement and frost.....).
In the end it turned out OK after glueing everything back together (a common practise amongst alpine collectors....)

Cheers

Harjo

Hi Jenna!
you can use for carbonates formic acid! The action is more slow and is impossible brocken the samples!

My worst error was cleaning 2 specimens of beautiful Crocoite crystals in a small/home ultrasonic cleaner, thinking it'd be safe to remove the matrix dust. Almost all of the crystals broke.

Chris. J
NZ

I once ultrasonically cleaned a micromount with small thin tabular beudantite/segnitite xls on mamillary goethite. After cleaning 90% of the xls were gone - they had been only very loosely attached to the goethite surface...

Putting a solid mass of fluorite into boiling H2SO4 wasn't so fun in the end...

I have a good one, I had four 15 cm plates of stilbite from Martin Marietta Quarry (11th Street Quarry) Hickory NC. I put them into Super Iron Out to get rid of Fe oxide staining. After a two day bath took them out everything was ok....2 weeks later they split like mica across the width of the 1.5 cm crystals....enough to make you want to cry!
Lucky for me that was only half of the total find, the rest still have Fe oxide spots on them!!!!!

KOR
Everett

I have used the vacuum cleaner to pull dust off of cyanotrichite and it worked quite well. When doing so, I took extra care to keep the nozzle quite a distance from the specimen and to control the both the specimen and the nozzle to prevent sudden, disasterous, attraction.

My worst two errors were both from the ultrasonic. These two specimen represent my only failures, while thousands of other specimens I have treated with the ultrasonic have benefited. The first was a 7 cm Moroccan Anglesite crystal that developed internal fractures after being cleaned in a warm ultrasonic bath. It is still a good specimen, but it had been free from internal fractures. I believe it was the heat and not the ultrasonic action that caused this. The other piece was a very nice historic Hungarian Manganite cabinet specimen, which, except for a couple of miniature and a few thumbnail specimens, dissolved into a pile of black mud. That one hurt.

Now, how about the worst trimming error?

Bob

Last week I busted 2 Trumbull scheelite crystals that had many multiple internal fractures. Each one was probably worth quite a bit (I was planning on trading them because I already have my prize) and hurt when they broke, but I kept the pieces, as do I with any fragment of scheelite that is lost in trimming.

have you tried EDTA in citric acid to get rid of Fe stains..EDTA is available at all chemical suppliers, it is Ethylene Diamine Tetra Acetic acid, it is a powder and has worked well for my "experiments" with minerals, you can also try Tartaric acid or dilute acetic (white vinigar) as you know many minerals have been lost due to cleaning, I always use a very small bit in a test tube..cold for a few hours, if no effect try warming..GENTLY. OR..failing no supplies of EDTA try ciric or tartaric acids, they are at least gentle-er than mineral acids, no doubt you know that, and you can use things like bleach (dilute) and Sodium Hydroxide dilute and sodium carbonate, i have used a method that is so gentle for cleaning..that is to use an aquarium pump with the mineral suspended in the fine bubbles, it cleans up better but not always purfect.

dave bradbury. devon.UK

EDTA does not effectively bind Fe3+ ions, because the hydroxide is still more stable than the complex. In a mixture of EDTA with citric acid, the latter does the job. For further explanation, see [www.mindat.org]

I prefer the term 'learning experience' instead of 'mistake'.

This spring a co-worker of mine learned about my mineral collection and wanted to donate her old collection to me. I was very surprised that the ~1000 cabinets were collected between roughly 1850 and 1920! Unfortunately all specimen were stored in open boxes and everything collected a century of gray dust. All specimen and labels were just ash gray without any color at all. So I spent much of my summer at the kitchen sink with soapy water and a toothbrush. I knew something was bound to get wrong, but how else to clean 1000 specimen without being able to see what you've got? Not all specimen and labels matched.
And indeed one faithfull evening I picked up a nice crystal, washed it gently, but instead of gray sludge my toothbrush produced white sludge.... I stopped cleaning immediately but the worse thing allready happened, I just flushed a 5mm thick coating of Goslarite from the type locality down the drain :-(
OK I am now left with the matrix, still an impressive 5cm hemimorphite and a little white coating of goslarite, but 95% of the Goslarite is gone, out into the sewage, the sea, a distant subduction zone, all ready to become a nice sofiite in some distant volcanic fumarol for the future generations of collectors......

About 25 years ago, when I was first getting seriously into mineral collecting, I was working in a commercial laboratory. Having access to professional grade facilities I figures that learning to clean and prepare my own mineral specimens would be a good thing. In those pre-internet days sources of detailed information on the subject were few. The exception being John Sinkankas' Gemstone and Mineral Data Book. This book contains a lot of useful information, including tips on how to clean various minerals. Unfortunately, one of the things he recommended was using oxalic acid to remove iron stain from fluorite. I found out that this is not such a good idea, but only after ruining a few good specimens.

Hey Jesse,
I ended up purchasing that book "AFTER" I tryed to clean a NJ natrolite in oxalic acid. Within 2 hours it was gone.
David

As a chemist it is particularly embarrassing to admit that I have screwed up on several occasions.

The first was in using HCl to dissolve off dolomite matrix from nice crystallised dendritic silver from Alva (some examples on this site). Most of the time it worked fine, but now and again the silver turned out black. It took me a while before it dawned on me that a few specimens had traces of sulphides. These were liberating H2S which in turn blackened the silver. I then switched to phosphoric acid and the problem ended, but not before some rather good specimens of this rare material were damaged.

The second was when I decided to remove a very slight iron stain from a particularly large and fine nailhead calcite crystal (several inches across on a bed of drusy quartz). It didn't really need it, I was just trying to be a perfectionist. So I plonked the piece in a bath of alkaline sodium dithionite & citrate, which is normally fine for this purpose. Unfortunately it was largely spent and was no longer alkaline. I did not realise this until I heard fizzing. Oops.

The third (and I still cringe at this one) was with fluorite. I was used to using HCl, even quite strong, to remove the more obstinate iron stains from North English fluorite, and had never had any problems. I had a really good fluorite from Gill Heads mine, Yorkshire. But there was just a hint of yellow from iron deep in the interior. As before my perfectionism got the better of me, as the piece really was not that bad, but I happened to have some HCl to hand so in went the specimen for half an hour. It went in smooth and lustrous. It came out dull and frosted. One of the best pieces I'd ever found ruined. Fortunately its partner from the same vug had not received this treatment and is one of my favourite Yorkshire pieces (see my gallery).

On a related note - was once trying to determine if an especially fine ettringite crystal from South Africa - you know, stout, transparent, about 5 cm long - was really ettringite or possibly charlesite. So, placed the whole into an SEM, turned on the vacuum, did the analysis, and then removed the specimen. Turns out that there was no issue with the identification, as the specimen was indeed ettringite; but the vacuum of the SEM sucked out some of the water or crytallization, leaving behind an ugly opaque, but still the same size, crystal! Could not be rehydrated even when placed in a 100% humidity environment. Moral - always look, or test, before you leap.

I tried to clean an ugly brown Calcite out of a lovely Mexican Amethyst Geode. No problem! Used HCl in the house. Took the calcite out beautifully but left ugly brown spots all over all of the kitchen appliances!

Moral of the story...Stay outside with that HCl !!

Fred

Dropped a hunk of massive magnetite into steaming oxalic. Ohhhh the acrid stink..

Stop! You are all making me cry!
This is the most painful thread I have read in ages. Oh the minerals were probably lamenting like the Wicked Witch in the Wizard of Oz~ "I'm Melting! Melting!"
"What a Cruel world....I'm melting"

Jenna,

If the zincite came from Franklin, New Jersey, you may have dissolved the calcite that fluoresces red; willemite fluoresces green, but not sure if HCl attacks the latter.

Dave

When I was young and stupid, I cleaned a lovely calcite specimen by dunking it in bleach. Nothing valuable, but it was a pretty piece, and I can still see that specimen like it happened yesterday.

Years ago I murdered my finest micro eudialyte rosette from Varennes, Quebec. She survived trimming down that hard, hard matrix, so should be perfectly safe in the old ultrasonic, right? Wrong... she went poof... painful.

Last year I lucked into a fairly unusual piece from the amethyst mines in Thunder Bay - a tiny chalcopyrite tetrahedron, all of 3 or 4 mm, altered, black, with unusually nice bright green malachite needles scattered on it, on a druse of very pale purple amethyst. Just a micro, no big deal, but very nice and quite rare for the locality. Problem was the 15cm chunk of matrix it was on... had to be trimmed! Ten seconds with the hammer and chisel later... the crack went right through the 3mm crystal... what are the odds of that... man was I pissed.

T

Here is one that happened to a friend of mine. He was doing some triming on a Brazilian tourmaline and quartz specimen. He had just taken the piece out of the ultrasonic cleaner and dried it off(he thought) and decided to put some super glue around the tourmaline to make sure it didn't fall off when he put it in the trimmer. Little did he know that super glue will react with water to form a white substance that expands. As the glue came in contact with some water he missed, we watched in horror as the expanding white goo pried the tourmaline and quartz apart, leaving him with a damaged specimen. He was able to repair the piece but now it was repaired and worth quite a bit less. Remember if you are going to do some trimming and want to use super glue just in case, make sure the piece is compleately dry first.

Hello!

On Timothy's case:

I guess Super Glue was Cyanoacrylic glue.Working with CA glue frequently since 1997 or so,I had no experience the glue reacted with water(maybe some mineral on the specimen,clay or something...).The glue reacts with Nitrocellulose diluter and it is disolvable in Acetone.It works very well with flat surfaces when they are dry and clean before application.

Using this glue to reinforce a specimen delicate crystals I don't think is a good idea.The glue has a higher grade of elasticity and a very thick layer should be applied to be helpful against ultrasonic vibrations.

Better don't use ultrasonic on fragile specimens,especially when they are valuable!

-Kostas.

About 20 years ago the world best gustavite xtls were found at Rotgülden, Salzburg, Austria [www.mindat.org].
Some were partially covered with calcite so I put about 20 specimen with 1cm long xtls in a box with HCl acid.
Unfortunately the acid was waaay too strong and dissolved all gustavite. Never found such good ones again.