The stones are sealed so that unwanted bacteria are likely to find it difficult to reproduce. However, this seal was already chipped in small areas at the corners as the stones arrived ... (What would not have been so bad, even if not one of, packed in too little bubble wrap stones would be broken cleanly in the middle .. .) But for the replacement arrived much faster than the first.
For EUR 12 not necessarily cheap, but because I had bought the pot 5 EUR at the flea market, it was portable.
