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Iron Out and Tap vs. Distilled/Filtered Water Question

Posted by Scott Rider  
Scott Rider November 14, 2017 06:52PM
I've been using SIO/IO for years now, and haven't had too many issues other than a very thin layer of white crust that would easily be wiped or scrapped off the surface.

However, earlier this year, my water has tasted odd, and there is definitely a build up on my faucets... I think the city changed its water source, of which I have not looked into, but the water sure tastes really odd.. My neighbor reported the issue and never got a reason of why...

Anyway, my question is that the recent build up of white film on my specimens due to the perceived increase in the waters hardness? My recent cleaning batches of Lake George/Devil's Head material have a nasty hard white encrustation of which I haven't had to deal with before. This was not a problem prior to my water changing... Before I would just would wipe or scrape the white film off easily, but now its much much harder, much more annoying and doesn't even scrape off easily anymore..

Should I keep using tap water or should I start using filters or bottled distilled water? Would the film decrease using filtered or distilled water? Or is it more a product of me using too much SIO? I don't think I added too much but I also haven't cleaned anything in last year until recently.. But I am certain the proportions are good.
Reiner Mielke November 14, 2017 07:04PM
The harder the water the more problems you are likely to encounter. I would recommend using rain water or dehumidifier water rather than expensive distilled water.
Scott Rider November 14, 2017 07:15PM
I hadn't thought of that... Rain probably won't work as I live in Denver, Colorado, rain is hard to come by... However, the dehumidifier is an interesting idea... I think my best bet however is using a Brita type filter an drawing water from that source... Probably be the best bet I am thinking...

Tonight I'll do an experiment and have 1 batch of acid water with the tap and 1 batch using Brita or Pur filtration. If I perceive no difference, then the calcium build up isn't the issue.. Its just most my friends use just plain ol' tap water and don't seem to have the issues I have...

One suggested using this, start with SI and through it into a CLR mixture, then many, many days of clean water to rinse everything off... Has anyone tried using SI then CLR?
Matt Neuzil November 14, 2017 07:32PM
Rain water would be a problem if in an area that receive acid rain?
Bob Harman November 14, 2017 07:51PM
Type and quality of the water used in cleaning and preparing mineral specimens has long been discussed on Mindat.

First of all, in most areas, acid rain (water) is not nearly the problem it was some years ago.
Hard water does leave a calcium lime scale in those areas where the water is really hard and there I would use dehumidifier water, or equivalent, when possible. In other areas, where the water is not so hard, tap water or dehumidifier water works just as well.
Let's be pragmatic here; cleaning and preparing hi end specimens demands some special treatments such as distilled water, but cleaning a routine ordinary quality specimen does just fine in clean tap water. In areas where the water is not so hard, don't waste time, money, and energy when tap water does just fine for routine specimens. CHEERS.......BOB
Scott Rider November 14, 2017 08:36PM
You make a fine point Bob. I think concentrating on using "clean" water on everything would be a massive waste of time and resources... Perhaps the best bet is to use "clean" water and IO only for the specimens I deem decent to higher-end. Considering most the stuff from pegmatite pockets are not that great, one could waste an enormous amount of time cleaning the crappier specimens. And most of my finds this year haven't been touched yet so I guess I need to start separating specimens in terms of quality, not locality.
Doug Daniels November 15, 2017 03:48AM
If you are in the U.S., and are using public water, I believe your State environmental division (or maybe the EPA) requires yearly analyses of the water. I get a publication each year showing the analyses of the common "baddies", of which hardness would be in there, but you might need to know how to read the analysis (chemistry and biology). And, they should have previous analyses on file to compare with what is now. And, you can always question them, saying that something ain't right. My in-laws had such a problem a few years back; nobody else in the neighborhood seemed to care. We told them who to contact at the State level for water quality; the problem got corrected rather quickly.
Harold Moritz November 15, 2017 02:25PM
I dont recommend using distilled or dehumidifier water when cleaning minerals because it is acidic! It may not matter so much when mixed with IO because that solution has buffers, which is probably why as your water is apparently hard you are getting precipitates. Acidity is mainly an issue with calcite/carbonates so use the dehumidifier water on your silicates etc. You can use IO on calcite because of the buffers in the solution, but dont rinse/soak calcite after with distilled or dehumidifier or rain water due to its acidity. Most water sold in gallon jugs is just bottled from some some public potable water system so is fine for general use or save this for the calcite only to lower your cost.
Reiner Mielke November 15, 2017 03:28PM
An acidity problem is easy to deal with just add a drop on ammonia and check the pH. Pool supply places can help you with that. In most caes the most important thing is hardness which results in water staining ( residue).
Douglas Schonewald November 15, 2017 04:25PM
The tap water in many areas is heavily chlorinated, especially during times of maintenance, heavy runoff, or flooding. I have noticed that if I can smell the chlorine in my tap water I get more of the green stuff on my specimens when using SIO. There are times when it is difficult to remove.

I bought a carbon block filter and installed it in an outside station. I hook the hose to the filter and run all my water through it that I use for cleaning. Maybe it is overkill, but it works well for me and I seem to have less problems than I did before.

I made the mistake, one time only, of cleaning specimens with HCL and not getting them completely neutralized. I then put them in SIO and tried to remove the remaining iron oxide. They ended up covered with a dark green crust that nothing would take off. I was never sure what it was, but I am certain it was related to the chloride remnants from the acid.
Harold Moritz November 15, 2017 04:44PM
Doug, that green stuff is an insoluble iron compound, nothing to do with chlorine. The chemistry is dealing with Fe3+ hydroxides, which give rusty stains, and Fe2+ hydroxides, which give green stains. The trick is to get insoluble Fe3+ into solution by converting it to soluble Fe2+, but without creating precipitates. Sometime instead of removing the rusty stain the IO turns it green, which is reversible by soaking in water again, or better a slightly acidic solution (I use HCl), but it doesnt create more crust.

In those situations where you have chlorine odor in water you also probably have high iron as well and probably other chemistry that is messing with the IO. The carbon will also remove the iron, but is an expensive way to do that, at least in large quantities (I know cuz I have a well with high iron and slightly low pH, which uses calcite for the pH and reverse osmosis using salt to remove the iron).
Douglas Schonewald November 15, 2017 05:58PM
Thanks Harold for the information. I'm not a chemist, and have no background, so I made some incorrect assumptions. The filter I'm using is pretty cheap (not sure how effective it really is) and the filters are inexpensive as well. Since I already have them I will continue to use them. Why does the green stuff seem to be so bad after the HCL wash and insufficient neutralization? Perhaps it is an effect of what is being cleaned more than what is in the water?
Steve Hardinger November 15, 2017 06:14PM
I use SIO with Los Angeles tap water, and have never had a problem with precipitates (white scum). Our water is rather hard (lots of dissolved calcium, iron, and magnesium). I've never felt the need for the expense of distilled water in either SIO or my ultrasonic cleaner. However any SIO soak is almost always followed by an equal or longer soak in clean (no SIO) tap water.

I have on a few occasions witnessed greenish stains appearing after SIO and clean water treatment. Especially with porous feldspars. As mentioned above, I attribute these to Fe2+ compounds of some sort. However, allowing the specimen to air dry for a day usually causes the green to disappear (I assume by air oxidation of Fe2+ to Fe3+).
Harold Moritz November 15, 2017 06:31PM
Doug, I'm not a chemist either (geologist) but have enough background in water chemistry having worked in the environmental field for decades. If you've got a system working, then keep doing it. It could be the stuff you're trying to remove that is the culprit. In many cases a white coating found "after" was there before, you just removed the rusty stain from it. It could be you just green-tinted an existing crust.

Steve, yes always soak in clean water after IO use, or any chemical. Air drying will reduce the green cuz all colors look darker when wet, but next time try a little acid in there if safe for the mineral. Could be that there is re-oxidation also. Yes, I've had the same problem with feldspars going green.
John Oostenryk November 15, 2017 07:09PM
Just thought I'd add a regional report here~
Living in NW IL my small city water does have plenty carbonate in it. 1 of the 3 wells is a half block away and I know the operating crew well enough, good guys and also have participated in random quality testing paid for by the city. All limits are properly met.
That all said- as I noted- we do have higher end of carbonate limit.
My tip off was when taking quartz out of the IO bath and putting in the clean clear (tap water) rinse, minutes later that water was cloudy white.
It would settle after a while, but be obvious when pouring out the rinse later... I had scrupulously removed the iron clays before IO- only transparent iron stain left to remove. This was clearly a IO residue.
I have switched to rinse water saved from dehumidfier for the rinse.
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