Sadly, I know almost nothing about modern Chinese or Japanese beads. I have, however, been collecting and studying East Asian ceramics for many years, and it seems to me that this bead in question fits quite nicely into one of the traditions of Japanese aethetics - that of wabi-sabi, the acceptance and celebration of the accidental and imperfect. The most exciting practitioner of it was Kenzan, arguably the greatest of Japanese artists, who was working in the early eighteenth century. I highly recommend Bernard Leach’s beautiful (and controversial) book on him, which discusses the style with the perception of the great artist that Leach himself was. I’ll attach a couple of images of Kenzan’s raku-ware pottery, one of them a lovely little bowl in the Brooklyn Museum. Kenzan worked in Kyoto, and the pottery of Kyoto today - Kyo-yaki - is characterized by a lot of Kenzan-style pottery. I wouldn’t be surprised if this bead came out of that sometime in the early to mid twentieth century. You can see from the first photo how Kenzan used Japanese characters in a freely decorative way that would be quite alien to a Chinese potter. I don’t know if the “characters” on the bead are legible or not, but they do resemble elements of Japanese script - not kanji, which are similar to Chinese characters, but hiragana or even katagana, which have evolved quite differently.

Cheers,

Will