Hi Anna, 

Thanks for pointing this out as it wasn't clear -

Le moule = a cake tin or a mould ( mold in American English) or a  cast which gives some medium its shape

La moule = a mussel

I have removed the other example as it created confusion.

To say mildew/ mold (the fungus), you would use 'moisissure' or 'mildiou'

but not relevant here.

Hope this helps!