silicone mold

Hello! 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...

I've got eight grandsons of which five are eight or less. Toy cars of every size, color and trademark are extremely popular and I thought a soap car might be interesting. This is my second try (the first one was found too small for a soap bar in their family).

I want to make a CP salt/spa bar and have a salt layer on bottom, but I want to do the reg recipe on top where the flower design is, (which means on bottom since I'll be pouring into the silicone sunflower molds.) Will I pour my reg batter in and then wait until it hardens somewhat.... add the...