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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 《Limited to 9 Stones》Blue Gem Gacha💎Paraiba Tourmaline (CuO:2.2%.MnO:3.5%)・Hauyne・Benitoite・Apatite《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 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 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 Pink tourmaline 0.795ct loose
Sold out Pt900 ブラジル産パライバトルマリン 0.11ct リング
Sold out 【Sales start 10 PM, May 17th】《Limited 12 Gems》Win a Shimizu Kiseki Sakura In-cut Diamond! 💎 Tourmaline Gacha (plus a bonus Sanje Tourmaline)《Multiple Purchase Discount Available》
Sold out ブラジル産パライバトルマリン 0.177ctルース
Sold out モザンビーク産パライバトルマリン 1.581ctルース
Sold out Brazilian Paraiba Tourmaline 0.216ct loose stone (CuO:1.2%, MnO:2.7%)
Sold out 【12562820掲載】ブラジル産バイカラートルマリン 7.445ctルース
Sold out 【12562810掲載】メキシコ産カンテラオパール 8.097ctルース
Sold out メキシコ産カンテラオパール 2.096ctルース
Sold out メキシコ産ウォーターオパール 1.018ctルース
Sold out 【12562701掲載】ブラジル産バイカラートルマリン 4.554ctルース
Sold out 【12562697掲載】トルマリン 5.620ctルース
Sold out ペルー産バイカラーブルーオパール 4.067ctルース
Sold out 【12562647掲載】ペルー産バイカラーブルーオパール 3.757ctルース
Sold out 【12562646掲載】ペルー産バイカラーブルーオパール 2.707ctルース
Sold out アフガニスタン産インディゴライトトルマリン 1.729ctルース
Sold out メキシコ産ファイアオパール 1.104ctルース
Sold out ケニア産クロムトルマリン 0.501ctルース
Sold out Green tourmaline 2.144ct loose
Sold out Australian black opal 0.232ct loose stone
Sold out 【12562555掲載】オーストラリア産ブラックオパール 0.248ctルース
Sold out 【12562533掲載】オーストラリア産ブラックオパール 0.427ctルース
Sold out 【12562530掲載】オーストラリア産ブラックオパール 0.784ctルース
Sold out オーストラリア産ブラックオパール 3.871ctルース
Sold out 【12562400掲載】メキシコ産オパール 0.265ctルース
Sold out 【12562398掲載】メキシコ産ファイアオパール 0.291ctルース
Sold out ウォーターメロントルマリン 3.403ctルース
Sold out オーストラリア産シェルオパール(貝オパール) 96.177ct原石
Sold out バイカラートルマリン 0.974ctルース
Sold out K18YG ベニトアイト 0.342ct リング
Sold out 【12561176掲載】メキシコ産オパール(ファセットカット) 0.644ctルース
Sold out 【12561168掲載】メキシコ産ウォーターオパール(ファセットカット) 0.349ctルース
Sold out 【12561913掲載】オーストラリア産ブラックオパール 0.221ctルース
Sold out Australian boulder opal 15.004ct loose stone
Sold out Mexican Fire Opal 0.281ct Loose

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.