White residue on my Silicone moulds

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Aug 12, 2022
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I just found this whitish residue on my silicone moulds. This is after it has been soaked and washed with soap. When I googled it, it said it was Calcium Sulfate. I just wanted to know if this residue would be detrimental to the next batch of soap I make in them. Google suggests certain cleaning methods which I can do but I don't want to end up with soap that reacts to this!
Attaching a photo for your reference. Thank you in advance!

Ps. Rubbing alcohol seems to be making it disappear too.

WhatsApp Image 2022-12-01 at 12.45.59 PM.jpeg
I put mine in the dishwasher and this should rinse away. Even so, sometimes I need to give them a wee wipe out with a wet/damp kitchen towel. Some types of silicone tend to do this more than others. I have some that pretty much end up squeaky clean after unmolding - like it was just brand new and never used ( they tend to be the more expensive molds).
Ok thank you! I was just worried it might react with the soap! Ive managed to clean it off after soaking it in warm water with vinegar and soap, followed by a rinse in the dishwasher.

thank you all again :)

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