Best Way to Clean Aragonite/Calcite
21st Aug 2018 16:02 UTCScott Rider
What would be the best way to go about cleaning the dirt off? I was thinking oxalic acid probably would work. I was told that would not affect calcite, so I assume it wouldn't harm the aragonite either? Anyone have any better ideas? Or is oxalic the way to go?
Side note: I can't really experiment yet, I am in the middle of selling my house (closes today!) and moving into my new home on Sept 22nd. But I figured I'd ask now and be ready when I move... Below are some of the finds:
Thanks Bob for the suggestions, I'm very excited that I've finally sold the house and moving on to the next chapter of my life!! Going prospecting/mining has kept me sane during this process, as selling and buying homes is not fun...
As for the specimens, I shall attempt to soak a few of the smaller specimens in warm water/soap, and then trying the vinegar solution as well. I have used vinegar in the past, but for much longer than you suggest. I think that is a good idea to do a short exposure, then rinse, and then probably repeat if there is some dirt. The majority of the dirt cleans off just by rinsing in water with no soap. But what is left isn't as easy to remove.
I have pieces up to about a foot long, so I'll have to experiment with the lighter and lower end ones first. I prefer not using acids unless its absolutely necessary as I would like to retain the luster. However, I have had luck removing clay and organic dirt from specimens with oxalic acid from my pegmatite finds. That is why I was thinking that may work, but I fear it'll kill the luster of the crystals so I'll let my friend try that solution out first. I don't think the dirt is organic in origin though, but the dirt is heavy with manganese oxides (and probably iron oxides as well). But, I am unfamiliar with how oxalic acid works with manganese oxides.
I was also thinking about an ultrasonic cleaner (not just for these but for future finds as well). Any suggestions on a good one that doesn't break the bank!
Here are two of the larger specimens. The larger one is in excellent condition, however, its nearly impossible to tell as its coated with that dirt, but it also seems to have some botryoidal material over some of the terminations that doesn't resemble the dirt that is all over the rest of the specimen. Perhaps that is some manganese oxide mineral (like pyrolusite):
Close up of the better one:
As for the specimens, I shall attempt to soak a few of the smaller specimens in warm water/soap, and then trying the vinegar solution as well. I have used vinegar in the past, but for much longer than you suggest. I think that is a good idea to do a short exposure, then rinse, and then probably repeat if there is some dirt. The majority of the dirt cleans off just by rinsing in water with no soap. But what is left isn't as easy to remove.
I have pieces up to about a foot long, so I'll have to experiment with the lighter and lower end ones first. I prefer not using acids unless its absolutely necessary as I would like to retain the luster. However, I have had luck removing clay and organic dirt from specimens with oxalic acid from my pegmatite finds. That is why I was thinking that may work, but I fear it'll kill the luster of the crystals so I'll let my friend try that solution out first. I don't think the dirt is organic in origin though, but the dirt is heavy with manganese oxides (and probably iron oxides as well). But, I am unfamiliar with how oxalic acid works with manganese oxides.
I was also thinking about an ultrasonic cleaner (not just for these but for future finds as well). Any suggestions on a good one that doesn't break the bank!
Here are two of the larger specimens. The larger one is in excellent condition, however, its nearly impossible to tell as its coated with that dirt, but it also seems to have some botryoidal material over some of the terminations that doesn't resemble the dirt that is all over the rest of the specimen. Perhaps that is some manganese oxide mineral (like pyrolusite):
Close up of the better one:
