This is a coaster with the letter "L" cut out of it. It is shaped like a puzzle piece in order to connect more of them together to form a word. For now it is meant to form the word "LOVE" with 3 other pieces, that you will have to order separately. By that you can also choose to go for a mix of colours, like you can see on the picture. The coasters are about 10cm long on each side.
Even though they are coasters, given that they are made of ceramics, they are very fragile and I would not recommend to actually put anything on them. They are more meant to be a decorative piece.
And just to make sure, this is only one puzzle piece, not the full set.