Coming soon

American Herkimer Diamond (Rock Crystal) 5.3mm/0.594ct Loose Sale price¥7,980

Lottery Sale ⑧ [For Winners Only] [Listed as 12563226] Kochi Prefecture Boke Coral (Sango) 7.900ct Loose Stone Sale price¥59,800

【Lottery Sale ①_202608_05】K18WG Diamond 0.50ct Half Eternity Ring Sale price¥128,000

コロンビア産パイライト・雲母インエメラルド 5.5mm/0.614ctルース鑑別書

[Published on 12563914] Loose Colombian Pyrite and Mica in Emerald, 0.614 ct Sale price¥45,800

[Item 12564087] Kochi Prefecture Boke Coral (Sango) 15.237ct Loose Stone Sale price¥69,800

カメレオンダイヤモンド 0.212ctルース(LIGHT BROWNISH GREENISH YELLOW（カメレオン）, SI-1)

[Published on 32501973] Chameleon Diamond 0.212ct Loose (LIGHT BROWNISH GREENISH YELLOW (Chameleon), SI-1) Sale price¥64,800

オレンジダイヤモンド 0.348ctルース(FANCY VIVID YELLOW ORANGE, VS-1)

[Featured in 32501971] Orange Diamond 0.348ct Loose Stone (FANCY VIVID YELLOW ORANGE, VS-1) Sale price¥128,000

イエローダイヤモンド 0.144ctルース(FANCY VIVID YELLOW, SI-2)

Yellow Diamond 0.144ct Loose (FANCY VIVID YELLOW, SI-2) [Listed as 32501969] Sale price¥55,800

[Listed as 12564020] Hackmanite 0.300ct Loose Stone Sale price¥59,800

【12548939掲載】マダガスカル産ラズライトインクォーツ 1.600ctルース

Lazurite in quartz from Madagascar 7.5mm/1.600ct loose Sale price¥18,800

Brazilian bicolor tourmaline 7.489ct loose Sale price¥39,800

ファンシーディープイエローダイヤモンド 3.6mm/0.190ルース(FANCY DEEP ORANGY YELLOW, SI2)

【#202607AkihabaraPopUpTakeOut】90002505NewYearLuckyBag2025_【On sale Dec 14, 10 PM JST】Fancy Deep Yellow Diamond 3.6mm/0.190ct Loose (FANCY DEEP ORANGY YELLOW, SI2) Sale price¥39,800

イエローダイヤモンド 0.245ctルース(FANCY INTENSE ORANGY YELLOW, SI1)

【#202607AkihabaraPop-upOutOfStock】【Shinjuku Marui Annex 202605 OutOfStock】【#202604KobeOutOfStock】【#202509ShinjukuMarui OutOfStock】Yellow Diamond 0.245ct Loose (FANCY INTENSE ORANGY YELLOW, SI1) Sale price¥55,800

[#202607 Akihabara Pop-up Store - Currently Removed from Stock] [12563475 Posted] Mahenge Spinel (Pink Spinel) from Tanzania 0.492ct Loose Stone Sale price¥49,800

[#202607 Akihabara Pop-up Store - Currently Displayed] [12563067 Listed] Padparadscha Sapphire 0.649ct Loose Stone Sale price¥128,000

[Lottery Sale 0628_08] Unheated Kashmir Sapphire 0.160ct Loose GIA Sale price¥98,000

ダイヤモンド 4.45mm/0.324ctルース(D, VVS1, 3Excellent) GIA&中宝

[Lottery Sale 1_202608_11] Diamond 4.45mm/0.324ct Loose (D, VVS1, 3Excellent) GIA & CBT Sale price¥98,000

ダイヤモンド 4.42mm/0.330ctルース(E, VS1, 3Excellent) GIA

【Lottery Sale ①_202608_10】Diamond 4.42mm/0.330ct Loose (E, VS1, 3Excellent) GIA Sale price¥98,000

インターナリーフローレスダイヤモンド（H&C） 3.9mm/0.215ctルース(E, IF, 3Excellent H&C) GIA

[Lottery Sale ①_202608_09] Internally Flawless Diamond (H&C) 3.9mm/0.215ct Loose (E, IF, 3Excellent H&C) GIA Sale price¥75,800

[Item 12564022] Tanzanian Mint Diopside 0.794ct Loose Stone Sale price¥22,800

Zoisite from Tanzania, 0.643 ct loose Sale price¥18,800

[Listed as 12564065] Brazilian Tourmaline Cat's Eye 0.689ct Loose Gemstone Sale price¥11,000

[Published as 12564054] Kochi Prefecture Coral 8.132ct Loose Stone Sale price¥69,800

[Published as 12564055] American Red Beryl 0.239ct Loose Stone Sale price¥69,800

[12564014 listed] Madagascar Royal Blue Sapphire 0.559ct Loose Stone Sale price¥45,800

[Posted as 12563996] Australian Black Opal 1.029ct Loose Stone Sale price¥29,800

[Posted on 12563959] Madagascar Padparadscha Sapphire 0.164ct Loose Stone Sale price¥36,800

コロンビア産パイライト・雲母インエメラルド 5.0mm/0.500ctルース鑑別書

[12563912 listed] Colombian Pyrite and Mica in Emerald 0.500ct Loose Stone Sale price¥39,800

Loose White Diamond 0.108ct (FANCY WHITE, I-1) Sale price¥55,800

diamond Sale price¥45,800

【#202607 Akihabara Popup Outtake】【12562793 Listed】Unheated Brazilian Imperial Topaz (Sherry Color) 0.459ct Loose Stone Sale price¥32,800

[#202607 Akihabara Pop-up Store - Currently out on loan] [Listed as 12563392] Tanzanian Red Spinel 0.291ct Loose Stone Sale price¥35,800

[On sale August 16th at 10 PM JST] Limited to 4 stones: Swiss Blue Topaz (Star of David/Hexagram Cut, approx. 8mm) [Multiple purchase discount available] Sale price¥5,980

Brazilian Paraiba Tourmaline 0.068ct loose stone Sale price¥61,800

[Lottery Sale 0707_06] Kunzite from Afghanistan, 69.722ct Loose Stone Sale price¥258,000

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） 0.459ctルース

[Lottery Sale 0707_08] Madagascar Bekily Blue Garnet (Color Change Garnet) 0.459ct Loose Stone with Certificate Sale price¥69,800

[Lottery Sale 0707_09] Unheated Burmese Sapphire 0.210ct Loose GIA Sale price¥69,800

【Lottery Sale 0731_08】Brazilian Emerald Cat's Eye 6.083ct Loose Gemstone with Japanese and German Gemological Report Sale price¥258,000

インターナリーフローレスダイヤモンド（H&C） 3.8mm/0.206ctルース(D, IF, 3Excellent H&C)

[Lottery Sale 0731_12] Internally Flawless Diamond (H&C) 0.206ct Loose (D, IF, 3Excellent H&C) Sale price¥89,800

[Lottery Sale 0731_09] Burmese Ruby 1.020ct Loose Stone GIA Sale price¥188,000

[Lottery Sale 0628_05] American Neptunite 0.374ct Loose Stone with Gemstone Identification Report Sale price¥79,800

【Lottery Sale 0428_2_05】American Neptunite 0.859ct Loose Gemstone with Certificate Sale price¥128,000

Pt900 カンボジア産ラタナキリブルージルコン 2.22ct・ダイヤモンド0.38ctリング中宝ソ

[Lottery Sale 0725_14] Pt900 Cambodian Blue Zircon (Ratanakiri Blue) 2.22ct Ring with GIA Report Sale price¥158,000

[Lottery Sale 0725_10] Unheated Mozambique Pigeon Blood Ruby 0.430ct Loose Gemstone AIGS Sale price¥98,000

[Lottery Sale 0725_11] Burmese Pigeon Blood Ruby 0.450ct Loose AIGS Sale price¥98,000

[Lottery Sale 0718_08] Tanzanian Pink Zoisite 0.419ct Loose Stone with Gem Identification Report Sale price¥69,800

[Lottery Sale 0725_03] Tanzania Purple Spinel 0.427ct Loose Stone with Certificate Sale price¥29,800

【#202607 Akihabara Pop-up Store - Currently out for display】【12563131 Posted】Brazilian Santa Maria Aquamarine 0.299ct Loose Stone Sale price¥19,800

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.