PROBLEM TO BE SOLVED: To provide a pearl nucleus including, in the inside thereof, an electronic marker capable of writing and reading information such as an appraisal evaluation result and production history of the pearl, and a method for producing the pearl nucleus, and to provide a pearl using the pearl nucleus while securing practical utility.SOLUTION: A pearl nucleus 20 includes: an electronic marker 3 capable of writing and reading information, in a storage part 4 disposed at a position eccentric from a center O and a pearl layer 60 formed on an external surface thereof. The pearl nucleus further includes a weight adjustment part 6 that, when the pearl nucleus 20 is divided into two parts on a plane passing through the center O and not including the electronic marker 3, differentiates the weight of the part at the side including the electronic marker 3 from the weight of the part without including the electronic marker 3.COPYRIGHT: (C)2014,JPO&INPIT【課題】真珠の鑑定評価結果や製造履歴などの情報を書き込み、読み取りすることができる電子標識をその内部に備えた真珠核と真珠核の製造方法、さらに、その真珠核を用いた真珠を、実用性を確保しつつ得ること。【解決手段】情報の書き込みと読み取りが可能な電子標識3が、中心Oから偏在した位置に配置された収容部4に内蔵され、外表面に真珠層60が形成される真珠核20であって、前記真珠核20を、中心Oを通り、かつ、前記電子標識3を含まない平面で2つの部分に分割した場合に、前記電子標識3が含まれる側の部分と前記電子標識3が含まれない側の部分との重量を異ならせる重量調整部6を備えている。【選択図】図4
