It was a great birthday gift for my wife. The cup's surface is not smooth, I am not sure what the material is. We rather dont put it in a dishwasher.
We're pleased to hear that you liked what you got for your wife's birthday! The surface of this product isn't smooth because it is a piece that retains the texture of pottery. Yes, we would recommend hand wash even tho it is dishwasher safe as pottery is more prone to chipping than porcelain. Please feel free to contact us if you have any questions! Thank you for shopping with us!