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10月誕生石

October birthstone

October's birthstone is opal tourmaline .

Opal is known for its play-of-color effect, which shows an aurora-like glow of seven colors on its surface, but some types do not show this play-of-color effect. Not only are there many types, but each one has a different play of color, so I think it's perfect for those who like unique gemstones.

Tourmaline is a gemstone with so many color variations that it is said that there is no other color. Some are called by different names depending on their color, such as Paraiba tourmaline and rubellite . Some stones have multiple colors in one stone, and others look like watermelons, so I think it's fun to collect a variety of stones and enjoy the different colors.

Karatz GemMagazine
" List of October birthstones and birthstones "

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Sold out Blue Stone Gacha💎 (Brazilian Paraiba Tourmaline, Mozambique Paraiba Tourmaline, German Auchenite, Benitoite) {Multiple Purchase Discounts Available}
Sold out Limited Edition of 11 Rare Stones! 💎 Two 0.23ct Paraiba Tourmalines from Batalha, Brazil, a Pink Diamond, and a Benitoite Loose Stone. Discounts available for multiple purchases.
Sold out Mini Kite Cut Loose Stone (Includes 2 Paraiba Tourmalines, Green Beryl, Ruby, Peridot, etc.) {Multiple Purchase Discounts Available}
Sold out Limited to 8 stones: Mexican Hyalite Opal Loose (Large 4ct, Fluorescent even in sunlight) Multiple purchase discounts available
Sold out Limited to 15 stones, 1 loose Australian iron opal stone, multiple purchase discounts available
Sold out Limited to 8 stones: Ethiopian black opal (heat-treated, identification instructions included, average 2ct, approx. 11x8mm) 1 loose stone (multiple purchase discounts available)
Sold out Panda Cut Gacha💎 Brazilian Paraiba Tourmaline (0.226ct/CuO: 0.7%, MnO: 2.5%) - 1 Stone, 5 Panda Cut Stones (Multiple Purchase Discounts Available)
Sold out Limited to 9 stones: Carving Gacha (Opal, Tourmaline, Tsavorite Garnet) 1 loose stone (Multiple purchase discounts available)
Sold out Limited to 9 stones: 1 loose Australian opal (faceted cut) [Multiple purchase discounts available]
Sold out [Limited to 7 stones] Gem gacha💎 Australian opal or Mexican cantera opal 1 loose stone (with defects) [Multiple purchase discount available]
Sold out Limited to 5 stones: 1 Mexican Hyalite Opal loose stone (average 0.5ct) Multiple purchase discounts available
Sold out Fire Opal (Common Opal) 2 stone set《Discount available for multiple purchases》
Sold out New Arrival from Tucson - Limited to 8 Stones: 1 Loose Australian Black Opal (Lightning Ridge Origin) - Multi-Purchase Discount Available
Sold out Zambian Canary Yellow Tourmaline (4.0mm/Round Cut) Loose Stone - Limited 5 Pieces (Multiple Purchase Discount Available)
Sold out Limited to 4 stones: Carving Gacha (pink tourmaline, average 3.4 carats) 1 loose stone (multiple purchase discounts available)
Sold out Limited to 9 stones [Mr. Sanjay] Oil in quartz, spinel, yellow opal 1 loose stone (damaged) [Multiple purchase discount available]
Sold out 《Limited to 7 stones》1 stone tourmaline in quartz from Sri Lanka loose (8-9mm, octagonal cut)《Multiple purchase discount available》
Sold out Limited to 12 stones: Mexican opal (custom faceted cut) - 1 loose stone (multiple purchase discounts available)
Sold out ブラジル産インディゴライトトルマリン 0.105ctルース
Sold out Brazilian Paraiba Tourmaline (cabochon cut, approximately 2.2mm) 1 loose stone (multiple purchase discounts available)
Sold out Brazilian Paraiba Tourmaline (cabochon cut, approximately 2.2mm) 1 loose stone (multiple purchase discounts available)
Sold out Limited to 12 stones! Gemstone Gacha including Brazilian Paraiba Tourmaline rough stone 💎 1 rough stone (Multiple purchase discounts available)
Sold out メキシコ産カンテラオパール 6.112ctルース
Sold out Limited to 2 stones: 1 Australian opal loose stone (pear cut) Multiple purchase discounts available
Sold out ブラジル産パライバトルマリン 0.240ctルース
Sold out オーストラリア産ボルダーオパール 52.582ctルース
Sold out 【ダンデライオンカット】メキシコ産ファイアオパール 7mm《コラボ》ルース ワッペン付
Sold out 【宝石商の道具】加熱処理のエチオピア産オパール 1石(ブラックオパールとの見分けシート付) - カラッツSTORE
Sold out オーストラリア産ブラックオパール 0.256ctルース
Sold out Pink Diamond Loot Box💎 Fancy Orange Pink 0.188ct and other Fancy-colored pink diamonds (all stones sorted or certified) 《Multiple purchase discounts available》
Sold out K18YG ウォーターオパール(ファセットカット) 0.457ct リング 鑑別書
Sold out ブラジル産パライバトルマリン 8.863ct原石
Sold out ブラジル産パライバトルマリン 8.135ct原石
Sold out ルベライトキャッツアイ 1.180ctルース
Sold out グリーントルマリン 0.512ctルース
Sold out K18WG ブルーサファイア パライバトルマリン、アクアマリン、エメラルド、アイスブルーダイヤモンド(トリートメント)、ブルーサファイア、イエローサファイア、アパタイト、ペリドット、タンザナイト、ブルートパーズリング鑑別書
Sold out オーストラリア産ホワイトオパール 1.138ctルース
Sold out Pt900ブラジル産シーフォームトルマリン 4mm/0.32ct ・ダイヤモンド0.16ctペンダントトップ(ネックレストップ)鑑別書
Sold out K18YG ブラジル産パライバトルマリン 0.095ct ダイヤモンド0.097ctリングソーティング
Sold out ナイジェリア産インディゴライトトルマリン 0.341ctルース
Sold out ナイジェリア産インディゴライトトルマリン 0.308ctルース
Sold out ブラジル産パーティカラートルマリン 6.799ctルース
Sold out ブラジル産グリーントルマリン 1.940ctルース
Sold out 【スターインカット】メキシコ産ファイアオパール 7mm/0.678ctルース ワッペン付
Sold out K18 ブラジル産パライバトルマリン 0.080ct・ダイヤモンド0.56ctペンダントトップ(ネックレストップ)(CuO:2.3%、MnO:0.6%)
Sold out ブラジル産グリーントルマリン 0.906ctルース
Sold out ブラジル産ルベライト 0.285ctルース
Sold out ブラジル産トルマリンキャッツアイ 13.617ctルース

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.