Aluminum molds and EO

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SweetWaters

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Will the essential oils in bath bombs corrode aluminum molds during the molding process?

So a friend recommended that I purchase a spherical mold on eBay that she uses for bath bombs. The description said that the mold was stainless steel, but upon examining the pictures closer I have a gnawing feeling that they are actually aluminum ( I plan on doing further testing when they arrive). However, I had already purchased the molds before my skepticism kicked in. I have read that EO should never be kept in certain containers like aluminium because they will eat away at the container and leech metals. I would like to gauge a response on whether or not I should repurpose these molds. If the EO in my bath bombs will corrode the aluminum in any way then I'd rather not chance it.
 

DeeAnna

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I'd be as or more worried about the citric acid -- I know for certain that citric acid will corrode aluminum. The corrosion is not dangerous like mixing aluminum and lye, but it would be a quality control issue.

It may be you're worrying about nothing, however, since it sounds like you're raising concerns about this issue based on pictures alone. I'd want more information before I drew any hard conclusions. Look at your friends mold -- has it corroded? Talk to the seller.
 

MySoapyHeart

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I have several in aluminium, purchased from ebay, and here is my experience using them for over a year now:

Sellers on ebay (china sellers etc) always (!!) lie and say their molds are stainless steel, but they are NOT stainless steel. Especially if they cost $1 or around that price.
Stainless steel molds for bath bombs are much, much more expensive, around $10 for 1.
I love making bathbombs myself (use them as foot soaks as I don`t have a tub) I have made a looot of these babies.
But just for the record, I do not sell them, they are only for personal use and small gifts. If I were actually to sell them one day I would absolutely invest in pure stainless steel molds from a reputable seller that really sold stainless steel molds.

But when I got mine I already knew that they were aluminium because stainless steel doesn`t have that matted grey & velvety look with a curl on the bottom. Sellers they are sneaky and list it in the top info that they are "stainless steel", but scrolling down the page below the item, most of the time they write that it is actually aluminium.

I decided to get them as a test to see if anything would happen with them with frequent use and if they reacted with the additives in my bathbombs. I didn`t have enough funds at the time to get the real deal in stainless steel as shipping was $25 to Norway for 1 mold + cost of the mold.

So I went for it, paid $2 for 2 sets of 3. and I have now used them for making my bath bombs for over a year straight. They have not corroded or shown any signs of wear or anything going on with them because of the citric acid or oils.

They aren`t rusted, scratched or rugged to the feel, they are just as smooth as the day I got them. They actually look as new. I use essential oils like orange, lemon, Bergamott, etc.

But, I sure do keep an eye on them. I will invest in stainless steel soon, they look more sturdy too.
 

DeeAnna

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Great insight -- I learned something from your thoughtful post. Thanks, MySoapyHeart!
 

SweetWaters

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I'd be as or more worried about the citric acid -- I know for certain that citric acid will corrode aluminum. The corrosion is not dangerous like mixing aluminum and lye, but it would be a quality control issue.

It may be you're worrying about nothing, however, since it sounds like you're raising concerns about this issue based on pictures alone. I'd want more information before I drew any hard conclusions. Look at your friends mold -- has it corroded? Talk to the seller.
Thanks, DeeAnna! I didn't even consider the citric acid being corrosive! And oh yes, I am definitely jumping to conclusions :) I just happened to see a different seller on eBay with the same stock photos who had their product listed as 'aluminium'. But you're right that I could be worrying about nothing. I'm going to test the molds when they come in the mail so I can be certain of their properties.

I appreciate everyone's insight! And thanks for sharing your story, MySoapyHeart! You've put my soapin' heart at ease.
 

Seawolfe

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I have to say, our workboat is unpainted aluminium, and it works in a very harsh and salty environment. I just develops an oxidized coating that protects it, and then it's pretty inert. I'd actually almost prefer aluminium than some of the crappy stainless steel I've been coming up against. Just keep aluminium away from lye!
 

MySoapyHeart

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Thanks, DeeAnna! I didn't even consider the citric acid being corrosive! And oh yes, I am definitely jumping to conclusions :) I just happened to see a different seller on eBay with the same stock photos who had their product listed as 'aluminium'. But you're right that I could be worrying about nothing. I'm going to test the molds when they come in the mail so I can be certain of their properties.

I appreciate everyone's insight! And thanks for sharing your story, MySoapyHeart! You've put my soapin' heart at ease.
You are most welcome!:)
 
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