FMF - Friends of Minerals Forum, discussion and message board

[David]

Hello,
I have a question, hope you can help me. How would you clean a very sensitive acicular mineral like stibnite without damaging it? (I mean to remove dust and stains) What about a fluffy okenite or extremely fragile scolecite? I know it is best not to let the dust cover the specimens in the first place, but some of them were dirty when I acquired them. I suppose you’ve noticed by now that I have a crush on needle like minerals. Thank you all!

[Joseph DOliveira]

There are many techniques for cleaning delicate specimens and some can be rather destructive.

I generally start with a bath of soapy water, fill a container with water and some dish washing detergent, then you just swish the specimen around and the loose debris will fall off.

For dirt that is attached directly, I again use dish detergent but use a very soft artists paint brush and with gentle strokes, brush the specimen to remove the dirt.

I have also used a spray bottle that you squeeze with your hand to move dirt from very delicate acicular specimens. This worked very well on some pentagonite specimens that I cleaned recently. Again, use soapy water in the spray bottle then flush with fresh water to rinse. You can control the velocity of the water spray by limiting the pressure you squeeze the trigger with.

If you can afford it, an ultra sonic cleaner will also work very well on these types of specimens, many are available for approximately $50-$100 on line.

Probably the most useful tool for cleaning, is the high pressure water gun that is commonly sold on line. It is very good at blasting dirt from tight crevasses in specimens and is very good for removing some undesirable druzy coatings that may be attached. This gun works at a high pressure and should be used with caution as specimens can be destroyed or you can cut yourself with the spray. Once again the cost of this item is around $50-$90 and can be sourced on line.

One word of caution, I would be very careful in cleaning the okenite specimens as they are extremely delicate and could be damaged by many of these techniques.

Hope that helps,
Joseph

[David]

Thank you very much, I will have the ultrasonic cleaner in mind.
I have had no problem with cleaning hard crystals, but I wouldn’t apply any sort of pressure on soft acicular crystals. Now I’m focused in preserving them in suitable conditions, unfortunately previous owners weren’t that careful.
By the way, doesn’t water affect stibnite?

[Joseph DOliveira]

I've never had water affect any stibnite that I have cleaned. I clean it and dry it off with a soft towel, never noticed any effect on the crystals.

[Susan Robinson]

I think aurichalcite, cyanotrichte, and chalcotrichite can be included with the okenite as being far too delicate to immerse in water or try to clean in any way. Once the fine crystals are matted down, the damage is done.

[Peter Megaw]

You can try a vacuum cleaner. Fasten the nozzle to something...tape it to a chair for example...then starting at some distance from the nozzle...say 3 feet or a meter gradually move the specimen towards the suction. At a certain point you'll see the dust and loose crystals start to get sucked up. Rotate the piece until it's as clean as you can get it without sucking off the attached crystals. If the dirt is stuck on and doesn't budge stop.

I have had decent luck focussing the vacuum by taping a paper cup over the nozzle and then sticking a soda straw through the bottom of the cup. This gives a strong focused vacuum that lets you clean more selectively

[John Nash]

David, I also like acicular crystals. I like to swish them in a roomy bucket of warm soapy water while holding the specimen upside down (firmly) with minerals that form radiating clusters, so as to allow the dirt to flush out rather than accumulating in the base of the cluster.

Okenite would be very hard to clean. If you get it wet it tends to look matted after it drys. Maybe a dry cleaning fluid, but I'd try it on a piece you don't care about.

John

[Peter Megaw]

Okenite is cheap enough that it might not be worth the time or effort to clean one.

[cascaillou]

might be worth trying an air duster (i.e. pressurized gas used to remove dust from keyboards)