Product list

Brazilian Tourmaline (untreated) 5.120ct loose stone Sale price¥39,800

Brazilian Yellow Beryl 11.411ct Loose Stone, Japan-Germany Exchange Sale price¥25,800

South African Rhodochrosite 0.990ct Loose Stone by Nikkei Sale price¥128,000

Brazilian Indigolite Tourmaline 1.514ct Loose Stone, Japan-Germany Exchange Sale price¥55,800

Brazilian Particolor Paraiba Tourmaline 0.490ct Loose (Bicolor Paraiba Tourmaline) GIA Sale price¥398,000

Tanzania Bicolor Zoisite 0.278ct Loose Stone Sale price¥4,980

Tanzania Bicolor Zoisite 0.357ct Loose Stone Sale price¥6,980

Mozambique Aquamarine 4.9mm/0.463ct Loose Stone Sale price¥8,800

モザンビーク産ピンクトルマリン 1.634ctルース（CuO:0.1%,MnO:0.1%）

Pink tourmaline from Mozambique 1.634ct loose stone (CuO: 0.1%, MnO: 0.1%) Sale price¥29,800

[Lottery Sale 0731_06] Colombian Pyrite in Emerald 2.988 ct Loose Stone with Japanese and German Gemological Certificates Sale price¥228,000

[Lottery Sale 0731_10] Colombian Muzo Non-Oil Emerald 0.370ct Loose GIA Sale price¥298,000

[Lottery Sale 0818_07] Madagascar Bi-Color Sapphire 1.870ct Loose Stone with Gem Identification Report Sale price¥79,800

[Lottery Sale 0818_09] Brazilian Dioptase 1.608ct Loose with Certificate Sale price¥59,800

[Lottery Sale 0825_10] Colombian Non-Oil Emerald 0.090ct Loose GIA Sale price¥128,000

[Lottery Sale 0812_18] Zambian Non-Oil Emerald 0.540ct Loose GIA Sale price¥178,000

Tibetan bicolor andesine 0.755ct loose stone Sale price¥6,980

Pt900/Pt850 ピンクトルマリン 1.10ct ダイヤモンド0.02ctペンダント（ネックレス）鑑別書

[22602719 Posted] [Calafuri] Pt900/Pt850 Pink Tourmaline 1.10ct Diamond 0.02ct Pendant (Necklace) with Certificate Sale price¥98,000

K18WG アレキサンドライト 0.32ct ダイヤモンド0.29ctペンダントトップ（ネックレストップ）鑑別書

[Listed in 22602716] [Colorfuri] K18WG Alexandrite 0.32ct Diamond 0.29ct Pendant Top with Certificate Sale price¥128,000

K18WG アレキサンドライト 0.64ct ダイヤモンド0.04ctペンダントトップ（ネックレストップ）鑑別書

[Published in 22602715] [Colorful] K18WG Alexandrite 0.64ct Diamond 0.04ct Pendant Top (Necklace Top) with Identification Report Sale price¥228,000

Pt900 グロッシュラーガーネット 1.31ct ダイヤモンド0.24ctリング鑑別書

[Published as 22602712] [Colorful] Pt900 Grossular Garnet 1.31ct Diamond 0.24ct Ring with Appraisal Report Sale price¥128,000

[8/30 22:00 Release] Madagascar Sapphirine 0.164ct Loose Stone with Appraisal Certificate Sale price¥12,800

[Available 8/30 at 10:00 PM] Madagascar Sapphirine 0.145ct Loose Stone with Identification Report Sale price¥11,800

[On sale 8/30 at 22:00] Diamond 4.4mm/0.309ct loose stone (D, VVS-1, 3Excellent) Sale price¥79,800

【8/30 10 PM Release】Sphene from Zimbabwe 0.302ct Loose Gemstone Sale price¥8,800

[Available 8/30 at 10 PM] Colombian Mint Color Emerald 0.359ct Loose Stone Sale price¥12,800

[8/30 10:00 PM Release] Mexican Fire Opal 0.352ct Loose Stone Sale price¥7,980

[Available 8/30 at 10 PM] Zimbabwean Sphene 0.332ct Loose Gemstone Sale price¥9,800

[Available 8/29 at 10 PM] Madagascar Andalusite 0.454ct Loose Gemstone Sale price¥7,980

[Available 8/29 at 10 PM] Tanzanian Purple Spinel 0.751ct Loose Stone Sale price¥18,800

[8/29 10 PM Sale] Tanzanian Mint Garnet 0.296ct Loose Gemstone Sale price¥8,800

[8/29 10 PM Sale] Brazilian Lavender Quartz (Skorolite) 0.475ct Loose Gemstone Sale price¥7,980

[#202607 Akihabara Pop-up Store - Currently Removed from Stock] [Listed as 12555668] Cambodian Colorless Zircon 0.929ct Loose Stone Sale price¥9,800

[Camellia cut] Mexican fire opal 1.270ct loose with patch Sale price¥69,800

【#202607 Akihabara Pop-up Store - Currently Removed from Stock】【Listed on 12563192】Unheated Ruby 0.210ct Loose Stone Sale price¥62,800

【#202607 Akihabara Pop-up Store - Currently Removed】【Listed as 12563268】Rough Diamond (Sawable) from South Africa 0.271ct Sale price¥88,800

マダガスカル産ベキリーブルーガーネット（カラーチェンジガーネット） 0.284ctルース

【#202607 Akihabara Pop-up, Currently Out of Stock】【12563254 Listed】Madagascar Bekily Blue Garnet (Color Change Garnet) 0.284ct Loose Sale price¥59,800

マダガスカル産アンデシン・ラブラドライト（通称名レインボームーンストーン） 0.116ctルース

【#202607 Akihabara Pop-up Store - Currently Displayed Off-site】【Listed as 12563184】Madagascar Andesine-Labradorite (Common Name: Rainbow Moonstone) 0.116ct Loose Gemstone Sale price¥14,800

【#202607 Akihabara Pop-up Store - Currently Removed from Stock】【12563063 Listed】Padparadscha Sapphire 0.619ct Loose Stone Sale price¥138,000

Pakistani Peridot 5.2mm/0.562ct Loose Stone Sale price¥9,800

Royal blue sapphire 1.220ct loose stone Sale price¥258,000

[Lottery Sale ②_202608_08] Unheated Color Change Sapphire from Sri Lanka 1.140ct Loose Stone GIA Sale price¥258,000

[#202607AkihabaraPop-upExhibition][12563418Posted] Burmese Ruby 0.303ct Loose Sale price¥9,800

【#202607 Akihabara Pop-up, Currently Out of Office】【12563057 Listed】Sri Lankan Royal Blue Sapphire 1.060ct Loose Stone Sale price¥188,000

[#202607 Akihabara Pop-up Store - Currently Removed from Stock] [12554030 Listed] Alexandrite Cat's Eye 1.655ct Loose Stone Sale price¥98,000

Brazilian copper rutilated quartz 1.262ct loose stone Sale price¥6,980

Brazilian copper rutilated quartz 1.647ct loose stone Sale price¥6,980

Brazilian copper rutilated quartz 1.352ct loose stone Sale price¥6,980

[Published on 12563859] Australian black opal, 1.184ct loose stone Sale price¥45,800

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.