Learning Center What is a mineral?The most common minerals on earth Information for Educators Mindat Articles The Elements The Rock H. Currier Digital Library Geologic Time

Minerals by Properties Minerals by Chemistry Advanced Locality Search Random Mineral Random Locality Search by minID Localities Near Me Search Articles Search Glossary More Search Options

The Mindat Manual Add a New Photo Rate Photos Locality Edit Report Coordinate Completion Report Add Glossary Item

Mining Companies Statistics Users Mineral Museums Clubs & Organizations Mineral Shows & Events The Mindat Directory Device Settings The Mineral Quiz

Photo Search Photo Galleries Search by Color New Photos Today New Photos Yesterday Members' Photo Galleries Past Photo of the Day Gallery Photography

Discussions

💬 Home 🔎 Search 📅 Latest

╳Discussions

💬 Home 🔎 Search 📅 Latest

Groups

Recent Images in Discussions

Techniques for CollectorsRemoving mud from delicate epidotes

11th Aug 2018 14:37 UTCAqua marine

Hi

Acquired some epidotes covered with clay/mud. How to remove it. These have great luster once cleaned.

Video link

https://youtu.be/9HQx0-KXdSk

11th Aug 2018 15:40 UTCKevin Conroy Manager

Soak in water for a day, then put them in an ultrasonic cleaner.

11th Aug 2018 15:54 UTCAqua marine

I Dont have an ultrasonic cleaner.

What if i soak it in water for a week and then use water gun with low pressure.

How long should be enough, so that the mud comes off really easily?

11th Aug 2018 15:59 UTCPaul De Bondt Manager

If you ad some ordinary dish wash detergent to the water, it will increase the penetration in the clay.

11th Aug 2018 16:22 UTCKevin Conroy Manager

As Paul said, detergent will help. You'll probably need to experiment via trial and error how long you need to soak, and if the low water gun will work to your satisfaction. Definitely use low grade specimens (if possible) when experimenting!

11th Aug 2018 16:29 UTCBob Harman

Your example looks like it could clean up to be very nice.

For me, one of the most important steps would be to reevaluate the specimen after the initial cleaning to see how stout or fragile it really is. Then go from there to maximize the cleaning while keeping the specimen totally intact.

Here is what I would do. First soak in soapy water for several days. Add a small splash of bleach if you want. No need to rush this step.

Rinse by gently swooshing thru a bucket of clean rinse water.

Reevaluate to see how much crud was removed and how stout or fragile your specimen seems to be.

If stout enough, then, starting with the gentlest setting, use your high pressure cleaning gun, gently rinsing the whole time and very often.

If done well, I think, you might be very happy with the end result. CHEERS.....BOB

11th Aug 2018 17:49 UTCDonald B Peck Expert

Last week I used a dental Waterpic and it worked really well. The pressure can be adjusted and it delivers a pulsating stream. I would imagine that you could find one at a garage/yard sale or perhaps on ebay. As others have said, soak first, and start gently.

16th Aug 2018 15:11 UTCAqua marine

Well it turned out not just simple mud. It is really hard. Soaking it water didnt do much. Have to use acid.

Gave it to a professional cleaner. Its too valuable to mess with.

Will post the result once its done.

21st Aug 2018 12:07 UTCAqua marine

Here is it

https://youtu.be/kM6KTWBtMX8

I was expecting a lot more luster. I guess too much exposure to the acid was the cause.

21st Aug 2018 12:15 UTCBob Harman

AQUA MARINE, Looks like a superior specimen to me......sweet! CHEERS....... BOB

21st Aug 2018 16:40 UTCDonald B Peck Expert

Nice!!!! I agree with Bob, it is a superb specimen.

21st Aug 2018 16:52 UTCHiro Inukai

A very fine and rich specimen! Not sure what level of luster you were expecting--it seemed quite lustrous to my eyes. The before-and-after comparison is striking. I'd love to know how the professional cleaner did it. Trade secrets, perhaps?

22nd Aug 2018 19:22 UTCAqua marine

He won't tell which chemical he used. He doesn't have any abbrasive device nor any ultrasonic cleaner. So definitely acid or some chemical.

Anyways im happy with the result as i have quite a bunch of these. Bigger and smaller

22nd Aug 2018 20:29 UTCDoug Schonewald

Probably nitric acid since Epidote is insoluble in nitric acid (according to what I've found). Epidote is also insoluble in sulfuric acid but I doubt he used that. I know I wouldn't. I don't like sulfuric after working with it in industry for many years.

22nd Aug 2018 20:35 UTCHiro Inukai

Intriguing. If not a mechanical method was used, I wonder if certain hardened clays could be susceptible to immersion in a deflocculant solution, like sodium silicate. Most likely there are multiple chemicals or treatments involved.

22nd Aug 2018 20:45 UTCThomas Lühr Expert

Sodium dithionite in the usual mixture with sodium citrate and sodium hydrogencarbonate (a.k.a. Waller's solution) surpizingly works well with loosening stubborn clay.

25th Aug 2018 12:31 UTCAqua marine

Here is another piece

https://youtu.be/PakBMUsy6uA

As you can see its quite lustrous and shinny and gives glittering effect. So after cleaning this glittering should increase.

The other piece had same glitter but after cleaning it became slightly dull.

If we could retain the luster and remove the clay, this would result in a phenomenal mineral.

25th Aug 2018 14:38 UTCKevin Conroy Manager

Often when a secondary mineral is deposited there is a corrosive effect on the underlying mineral. When the secondary mineral is removed the portions of the original mineral under it simply aren't going to have the luster of the portions of the crystals that weren't covered. Also, sometimes the luster of a mineral isn't going to improve after cleaning. Regarding the luster of your epidote crystals (which I think is very good), I think what you see is what you get.

Cleaning will obviously remove the secondary mineral. It may be that the contrast of the epidote crystals with the secondary mineral made them look more lustrous, and the luster is the same now but it isn't as noticeable because the contrast isn't there. You can test this by taking a still photo of a specimen before and after cleaning. The camera and the piece has to be in the exact same position both times, with identical lighting orientation and conditions.

25th Aug 2018 21:02 UTCAqua marine

Yes it is quite possible wht Mr kevin has described. Lets see what we get with the second piece. I'll look for someone with a mechanical approach to see if we can get a better result.

But i doubt if ultrasonic cleaning can get rid of really stubborn clay. Will it?

Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 26, 2024 09:31:23

Go to top of page