These are a deck of Japanese cards, with which you could play the continental game of Tarot, or use them for divination, or I believe play a different card or board game also. But as just about everything written about them is in Japanese I'm not able to give much detail!
But the deck is 78 hexagonal cards, 2 inches across, and printed so as to suggest 3-D pathways as you lay down the cards.
They came in a two-part, slip-cased set, with a great looking book, but sadly I can't read any of it.
The ISBN I have is 978-4-568-50486-6 but I bought a set direct from Japan with the help of a friend and I don't know how easy they are to get hold of now. Perhaps a board game store would be able to help?