Vintage coaster set of 5 mid century 1960s and 50 similar items

Vintage coaster set of 5 mid century 1960s Black Green Palm Trees Handmade Japan. These appear to be handmade. The inlaid shell (possibly from abalone) that makes up the trunk and base of each palm tree on each coaster is different and unique from each other. See photos. Each coaster measures approx 3" across. There is some wear of the black lacquer paint on some of the coasters due to wear and age. These are minimal. See photos. Single owner, stored in non smoking home for over 60 years.