This is a pair of yunomi (tea cups) by Korean potter Ji Jae-byung (pronounced "Chi Che-byong" or "Lee Jae-byong"), a specialist in celadon. (He also seems to be known by the alias Ji Jae-seop.) My mother purchased these as a souvenir when she visited Korea in 1996, although they were a bit expensive at the time. She seems to have opened them, but they were ultimately never used and have been stored. A recently released Korean film (an old historical drama) features a vessel with a similar pattern to these items. Perhaps he is inheriting and spreading an ancient tradition. This is purely my speculation. Would anyone interested in Korean pottery or yunomi be interested? I will ship anonymously.