Special sponge for stone bathtub

[NaiceShoes]

I have moved into a house that has a freestanding bathtub made of crushed stone. The vendor left behind two sponges and said they are special ones for removing dirt from the grain. The thing is the sponge disintegrates after being used once so I need a supply of them not just two token sponges.

Does anyone know where I can purchase them from? They are not like normal sponges. They are almost like candyfloss. I've tried searching online but cannot find anything

Until you said they were like candyfloss I thought you were talking about Magic Sponges, which are very gently abrasive and made of melamine. Can you post a photo?

I think magic sponges? Buy them from eBay

You two beauties!! I've been scratching my head about this for weeks and asked on MN and got an answer in minutes! I just Googled Magic sponge and that's exactly what they look like. When I said candyfloss, I meant they are firmer than candyfloss but when I used one to clean the bath it kind of disintegrated rather than stayed whole like a normal washing up sponge would do. Thank you- off to order some!