We, CORE JEWELS have been building our unique concept of jewelry free from traditional concepts and theories through collaboration with contemporary artists in various fields, as well as designer brands, since our establishment in 2003. That has been possible because of the jeweler’s background of street culture.


Founder / Jeweler

Masanori Yamazaki

CORE JEWELS founder Masanori Yamazaki was born and grew up in Shinjuku which has been the base of his activity as a jeweler. He has experienced various cultures and values throughout his life in and outside of Japan. He has put himself in the center of Tokyo’s street culture since its genesis. Under the influence of the power, which is common among countercultures, he began to redefine and express things from his unique perspective. In addition to the strength and beauty Yamazaki has been pursuing, he was destined to be led to the diamond business in 1999. Since each diamond is unique, it is viewed as a symbol of individuality. The genuine value of diamonds really cannot be measured by the standard grading methods alone. Masanori focuses on the individual nature of each diamond and explores the potential of the jewelry by redefining its relationship with materials such as metal. Around the time of CORE JEWELS’s establishment in 2003, black diamonds were rarely used in jewelry. However, CORE JEWELS released its first collection using black diamonds as the keystones. CORE JEWELS, since its establishment, has been continuously presenting collections free from traditional concepts and theories, such as where jewelry has been fused with advanced technology.

Founder / Designer

Hitomi Matsumae

Hitomi Matsumae learned about jewels and jewelry making techniques at workshops. She has provided designs for Paris collections and major jewelry brands and worked on many haute couture jewelry items. Since Core Jewels establishment in 2003, she has been pursuing the creation of jewelry that brings excitement to daily life under the concepts, "abstract", "minimalist" and "contemporary". In order to create jewelry where her imagination can be freely expressed, she handles everything from drafting and graphic design to prototype creation using 3DCAD, so as to precisely express her obsession through the jewelry. Since 2019, instant and accidental shapes through distortion have been emphasized to create unique abstract sculptures. Such avant-garde jewelry created through a combination of abstract modeling and pop inspiration have been introduced to the world through her uncompromising will.


2003年、ブラックダイヤモンドをキーストーンに掲げたファーストコレクションを発表。以来、最先端テクノロジーを導入したコレクションなど唯一無二のジュエリーをはじめ、 現代美術家や各界のアーティスト、あるいはデザイナーズブランドとのジョイントワークなど、ジュエリーの概念を再構築してきたコアジュエルスの歴史とそのアーカイブス。