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cobalt spinel

Spinel is one of the birthstones for August. Among spinels, those that contain a large amount of cobalt and exhibit a bright blue color are called cobalt spinels. The shade of blue is thought to change depending on the cobalt content, and the darker the blue, the more valuable it is.

Karatz GemMagazine
" Cobalt Spinel "

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Sold out Cobalt Garnite 1 stone (discount available for multiple purchases)
Sold out Limited to 15 stones: Musgravite, Taaffeite, Cobalt Garnite, Spinel & Friends Gacha, etc. worth ¥60,000 (bonus: 1 Platinum Spinel) (Multiple purchase discounts available)
Sold out 【11/2 22時販売】《限定15石》ブルー石ガチャ(非加熱ブラジル産パライバトルマリン,パライバトルマリン,コバルトガーナイト鑑別書付,インディゴライトトルマリン・サファリン・ベニトアイト・アウイナイト)《複数購入割引有》
Sold out Limited to 10 stones: Blue Spinel Gacha, Cobalt Spinel (including color-shifting type), 2 stones with Japanese and German appraisal certificates, and a bonus synthetic cobalt spinel. Discounts available for multiple purchases.
Sold out Limited to 10 stones: Blue Stone Gacha (Paraiba Tourmaline, Cobalt Garnite, Indigo Tourmaline with Certificate of Authenticity, Zimbabwean Euclase with Certificate of Authenticity) (Multiple purchase discounts available)
Sold out Color Change Gacha💎 Burmese Color Change Zircon, Color Shift Sapphire, Color Shift Cobalt Spinel, and More (Multiple Purchase Discounts Available)
Sold out Limited to 10 stones: Blue Stone Gacha (0.088ct Paraiba Tourmaline from Brazil, Euclase from Zimbabwe, Cobalt Garnite) [Multiple purchase discounts available]
Sold out Limited to 2 stones: 1 Nigerian Cobalt Garnite stone (Multiple purchase discounts available)
Sold out ナイジェリア産コバルトガーナイト 0.299ctルース 鑑別書
Sold out タンザニア産コバルトスピネル 0.458ctルース
Sold out Pt950 スリランカ産コバルトスピネル 0.697ct リング
Sold out ナイジェリア産コバルトガーナイト 0.133ctルース
Sold out タンザニア産コバルトスピネル 0.284ctルース
Sold out ナイジェリア産コバルトガーナイト 0.242ctルース JTL鑑
Sold out スリランカ産コバルトガーナイト 0.214ctルース JTL鑑
Sold out スリランカ産コバルトスピネル 0.647ctルース
Sold out ベトナム産コバルトスピネル 0.075ct原石(カラーシフト)
Sold out 非加熱コバルトスピネル(コバルトブルースピネル) 0.740ctルース(シールドカット) GIA
Sold out ナイジェリア産コバルトガーナイト 0.707ctルース
Sold out Nigerian Cobalt Garnite 0.311ct Loose Stone JTL Catalog
Sold out 【スタッフセレクション】タンザニア産カラーチェンジコバルトスピネル 0.249ctルース(セミオーダーメイドセッ
Sold out コバルトガーナイト 0.251ctルース
Sold out K18コバルトスピネル0.154ct リング 日独付 - KARATZ STORE|カラッツSTORE
Sold out Pt900コバルトガ―ナイト0.04ct / 0.04ct ピアス - カラッツSTORE

KARATZ Custom Made

Why not take your favorite gemstone that you found at KARATZ and have it made into custom-made jewelry? It will be made by skilled Japanese craftsmen.
We carefully craft each piece of jewelry, starting with the stone setting, to match the individual characteristics of the gemstone.

KARATZ・Five Commitments

So that more people can feel closer to jewellery and enjoy it easily.
We will introduce KARATZ's thoughts on products, the attention to detail and efforts in selecting gemstones and creating jewelry.

KARATZ's Initiatives and Social Contributions

We will introduce KARATZ's efforts, including nurturing the next generation and business collaboration to develop the industry, and supporting children in Sri Lanka, the land of jewels.

KARATZ Books

These are books that KARATZ has been involved in writing, supervising, and planning. They are all books that allow you to enjoy gemstones from various angles. You can also purchase them directly.

jeweler's tools

For those who want to enjoy jewelry more but don't know what tools to use, we will introduce tools that are also used by KARATZ staff. You can also purchase them directly.