Birthstone list

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[Sale on 6/13 at 10 PM] Limited to 11 stones! Ametrine Sakura-cut Koshu-Kiseki-Kiriko plusthree Gacha (including flower cuts, usually priced at 29,800 yen), with a bonus mini ametrine stone. Multiple purchase discount available.

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[Sale on June 17th at 10 PM] Brazilian Swiss Blue Topaz 1.025ct Loose Stone

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[On sale June 21st at 10 PM] Teal Green Sapphire 3.1mm/0.142ct Loose Stone

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[On sale June 18th at 10 PM] Madagascar Bi-Color Sapphire 5.1mm/0.607ct Loose Stone

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[On sale June 14, 10 PM JST] Madagascar Bi-Color Sapphire 4.5mm/0.506ct Loose Stone

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[On sale June 14th at 10 PM] Madagascar Bi-Color Sapphire 5.3mm/0.741ct Loose Stone

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【Sales start June 14, 10 PM JST】Madagascar Bi-Color Sapphire 5.4mm/0.765ct Loose

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[On sale June 23rd at 10 PM] Madagascar Blue Sapphire 4.5mm/0.406ct Loose Stone

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[Sale on June 23 at 10 PM] Madagascar Bicolor Sapphire 4.7mm/0.488ct Loose Stone

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【さくらインカット】コンゴ産ピンクトルマリン 7.0mm/1.056ctルース　鑑別書

[Sakura Ingot Cut] Pink Tourmaline from Congo 7.0mm/1.056ct Loose Stone with Certification

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[On sale June 14th at 10 PM] Sri Lankan Moonstone 0.794ct Loose

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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） 1.904ctルース

【Sales start June 16, 10 PM JST】Madagascar Andesine-Labradorite (Common Name: Rainbow Moonstone) 1.904 ct Loose Stone

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[Sales on 6/13 at 10 PM] Madagascar Pink Sapphire 0.239ct Loose Stone, Japan-Germany Gemstone Institute certified

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【On Sale June 14, 10 PM】[ColorFleuri] K18 Pink Sapphire 0.452ct Pendant Top (Necklace Top) with Certificate of Authenticity

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Pt900 合成アレキサンドライト 1.08ctct ペンダントトップ（ネックレストップ）鑑別書

[Sale starts 6/18 at 10 PM] Colorful Pt900 Synthetic Alexandrite 1.08ct Diamond 0.06ct Pendant Top (Necklace Top) with Appraisal Certificate

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Unheated Brazilian Paraiba Tourmaline 0.088ct loose stone (CuO: 1.9%, MnO: 2.3%)

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[Sale 10 PM, June 26] Rough Russian Diamond (Sawable) 0.098ct (Trigon)

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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） 0.640ctルース

【Sale begins June 25th at 10 PM JST】 Madagascar Andesine-Labradorite (Common Name: Rainbow Moonstone) 0.640 ct Loose Stone

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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） 0.610ctルース

[On sale 10 PM JST, June 23] Madagascar Andesine-Labradorite (Common name: Rainbow Moonstone) 5.0mm/0.610ct Loose Stone

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グリーンダイヤモンド（トリートメント） 0.183ctルース(FANCY INTENSE YELLOW GREEN TREATED, VS1)

【On sale June 26th, 10 PM JST】 Apple Green Diamond (Treated) 3.6mm/0.183ct Loose (FANCY INTENSE YELLOW GREEN TREATED, VS1)

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Pt950 Brazilian Paraiba Tourmaline 0.043ct/Diamond 0.013ct Ring (CuO: 1.6%, MnO: 2.3%)

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Almandine Garnet 0.660ct Loose

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Bolivian Ametrine 16.867ct loose stone

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[Sale starts June 22nd, 10 PM] Colorful K18 Ruby 0.44ct & Diamond 0.18ct Ring with Appraisal Report

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K18PG 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）ペンダントトップ（ネックレストップ）鑑別書

[On sale June 22 at 10 PM] [Colorful] K18PG Andesine and Labradorite (common name Rainbow Moonstone) Pendant Top (Necklace Top) with certification

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[Sales start 10 PM JST on 6/22] Colorful K18 Ametrine Cat Motif Pendant Top (Necklace Top) with Appraisal

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[On sale 6/20 10 PM JST] Loose Diamond 3.4mm/0.144ct (I, VS1, Good)

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[On sale June 25, 10 PM] [Colorful] K14WG Black Diamond 0.89ct / Diamond 0.13ct Pendant Top (Necklace Top) with Certificate of Authenticity

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K18WG グリーンクォーツ・ダイヤモンド0.02ctペンダントトップ（ネックレストップ）

[On sale June 25th at 10 PM] [ColorFuli] K18WG Green Quartz and 0.02ct Diamond Pendant Top

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Brazilian Bi-color Paraiba Tourmaline 0.190ct Loose (CuO: 2.06% MnO: 1.31%) with Japan-Germany Gemological Analysis Report

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Tanzanite 0.760ct loose stone (sugarloaf cut)

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Limited to 10 stones: Brazilian Bicolor Tourmaline (Baguette Cut) - 1 loose stone. Discounts available for multiple purchases.

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フローレスダイヤモンド（H&C） 4.2mm/0.280ctルース(D, FL, 3Excellent H&C) GIA&中宝

【Lottery Sale 0620_09】Flawless Diamond (H&C) 4.2mm/0.280ct Loose Stone (D, FL, 3Excellent H&C) GIA&CGL

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フローレスダイヤモンド（H&C） 0.290ctルース(D, FL, 3Excellent H&C)

【Lottery Sale 0530_05】Flawless Diamond (H&C) 4.3mm/0.290ct Loose Stone (D, FL, 3Excellent H&C) GIA & Central Gem Lab

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インターナリーフローレスダイヤモンド 0.217ctルース(D, IF, 3Excellent H&C)

[Lottery Sale 0530_02] Internally Flawless Diamond 3.8mm/0.217ct Loose Stone (D, IF, 3Excellent H&C) GIA

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[On sale July 5th at 10 PM JST] Madagascar Padparadscha Sapphire 3.5mm/0.206ct Loose Gemstone (with Central Gem Lab certificate)

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[On sale July 5th at 10 PM] Mozambique Ruby 0.415ct Loose Stone with Appraisal

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[Lottery Sale 7][For Winners Only][Posted 12563498] Unheated Kashmir Sapphire 0.350ct Loose GIA

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[For sale on July 4th at 10 PM] Mozambique Ruby 0.300ct Loose Stone with Gemstone Report

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[On sale July 4, 10 PM] Burmese Ruby 3.1mm/0.120ct Loose Stone with Certificate

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Paraiba tourmaline from Brazil 0.056ct loose

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Pt900 エメラルド 0.30ct ・ダイヤモンド0.01ctペンダントトップ（ネックレストップ）

[On sale July 16th at 10 PM] [Colorfri] Pt900 Emerald 0.30ct & Diamond 0.01ct Pendant Top

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[On sale July 4th at 10 PM] Diamond 3.7mm/0.197ct Loose (K, VS-2, VeryGood)

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[On sale July 6th at 10 PM] Limited 1 set: 11-stone treated diamond set (approx. 1.2mm x 11 stones) [Multiple purchase discount available]

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[Lottery Sale_0612_08] Unheated Purple Sapphire 0.775ct Loose Gemstone - Houseki Kyo

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.