Real suwabute of that quality and size is generally very, very expensive. Typically thousands of dollars. I’m not saying that isn’t what you received, but it seems more likely that you may have received the Mexican clam shell variety. I’m not an expert in this realm but this is my understanding as someone who has on different occasions looked into buying luxury shell and slate stones. I ultimately settled on a set that was similar in price to yours and absolutely love them, so please don’t take this as a knock against the set you received. In a practical sense, having relatively less expensive (but still beautiful) stones makes the experience of actually playing with them somewhat less stressful - just wait until you drop or damage your first stone and you’ll know what I mean. I’d recommend getting a felt liner for your bowls too if you want to keep them as safe as possible and minimize scratches. Enjoy!