Rock there is some pyrite in this matrix. Will this cause more staining?


I also have another rock from the same location that is mostly pyrite with some kyanite in a quartzite matrix. Can this also be cleaned in this manner?

The best way to remove iron stain of silicate minerals is a bath in Dithionite, solved in a Wallers solution (look in the internet). Now in summer you can give the vessel with the solution in the open air because it smells not good. 20° C are necessary to make the process running. After 1 day the specimen should be clean.


Uwe Ludwig

Paul,


Just as an addition to Rock's advice. If you add some baking soda (sodium bicarbonate) to your Super Iron Out solution you will still get the cleaning effect but with a lot less odor. I use one part baking soda to one part Super Iron Out and it works well for cleaning iron stains off most minerals. You often must use multiple cleaning and rinse cycles if the specimen is heavily stained and soak/rise at least twice as long as you treat and change the rinse water at least once. Generally speaking you never can rinse too much. Many cleaning problems are due to not soaking/rinsing long enough in clean water.

Operation Specimen Ruin is now complete. Iron Out results:


What I was afraid of happened. The specimens were too fractured to be treated. I did two soakings and when I would rinse the water would start peeling away pieces of kyanite. The rocks were massive kyanite with rutile in pyrite dotted all over and ranged in size from a lemon to a cantaloupe. The largest one is still pretty much intact and I hope when it dries it will not be stained, but I fear it might be.


What is happening is that the iron out works within 5 minutes. It looks great until it dries and then it has some yellow discoloration.


I also dipped a pyrite/quartz specimen in the same solution (from another source) and it was cleaned in 20 minutes. I had earlier attempted to electroclean this but the quartz was stained orange from the iron. The iron out cleaned it no problem, and with no yellow discoloration when it dried.


The quartzite specimen is still stained and I will treat it in a harder solution next time.



Something good did come out of it though, I got one iridescent hematite shining.


Sometimes it is better to leave them alone. Thanks for the help everyone!

The large one did ok. A little stain on one tip, but I am not gonna chance it with another wash. A smaller one is also salvageable. I will try pictures later this week.

Rock, These rocks came from Graves Mtn which has such an abundance of pyrite that the sulfur collects on the rocks in a yellow powder. It is so prevalent that you can literally smell the sulfur on the rocks and in the mine itself.


It could be sulfur or it could be some other chemical...... knowing the area, sulfur is the logical choice. Will try to get pictures up tonight.

Rock I am trying to remove the yellow stains from a kyanite specimen that contains pyrite and rutile. Aside from the yellow stains there are some instances where the kyanite has turned brown. Let me post some pictures and then we can disect the stains and how to treat them.

The first picture is of the larger specimen and has none of the yellow surface staining left over from the wash. It does however have little brown spots which I think are a result of iron staining the blades . It appears to be trapped underneath them. This brown stain appeared after I treated the specimen.


The second pic is the quartzite and it still has some yellow tinge left and I plan on washing it in a hotter harder solution.


The third shows exactly what the yellow stains look like after they have been dipped. The staining actually appears once the minerals have been dipped and rinsed and then dried.

Here is the hematite that cleaned up nicely.

If you are having trouble with the stain reforming on drying, don't give the specimen a chance for more precipitation or oxidation: get the water off immediately. First, rinse off the iron out with clean water. Next, either blow dry with compressed air, or (probably better) rinse with an organic solvent like ethanol (denatured alcohol) or acetone and then let dry. This should remove the water, which might be promoting oxidation of pyrite or causing iron salts to leach out from inside the specimen. I haven't ever tried this, but it seems like it can't hurt.

Good call Noah. Wood turners use a similar method of immersing blanks into alcohol and letting it displace the water.


I mat try to make a concentrated paste of Iron out and gently brush on to the spoecimen and let it soak for a few minutes and then see how it handles.

Ascorbic acid (aka vitamin c pills) lift it in seconds no scrubbing