DSF

I gave a friend some mugs that I had cocked up, I was using them but had so many I was glad to give them away. Today he popped into see me and said that all the mugs I had given him had hair line cracks inside, when he made coffee and washed them the coffee had left fine black lines where he said the hair lined cracks were, the mugs didn't leak but he said that they could harbour germs. I've never had a customer say anything like that. but I worried in case they not saying. Can any one shed light on this. I made 3 mugs of coffee to test the ones I had but nothing.

i had this few times with mugs. its not crack of the mug. it looks like coating cracks.

I didn't realize that they are coated inside. Is he right about the germs

just a glaze inside I think you'll find.

Thanks for that in everybody, I would hate to think that I was selling something under par, mind you he did say his kettle was boiling to long and the plug was to hot.

Well, I have seen many mugs in my life and a lot have a 'stained' bottom where it does appear to be scratches. However I would think that most germs would die a) everytime you poured boiling water in and b) everytime they were subsequently washed. I doubt that there is much risk to health from a mug with cracks in the bottom. I have heard that this crazing in the bottom of mugs can occur if you cool your sublimated mugs in cold water instead of fan cooling or cooling in warm water.