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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 5 stones: 1 Mexican Hyalite Opal loose stone (average 0.5ct) Multiple purchase discounts available

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》

Fire Opal (Common Opal) 2 stone set《Discount available for multiple purchases》

Sold out [Sales begin June 12 at 10 PM JST] Blue Gem Gacha 💎 Featuring Brazilian Paraiba Tourmaline (CuO: 1.5%, MnO: 3.2%) normally priced at 35,800 JPY, Zimbabwean Euclase, and more! 《Bulk purchase discounts available》

[Sales begin June 12 at 10 PM JST] Blue Gem Gacha 💎 Featuring Brazilian Paraiba Tourmaline (CuO: 1.5%, MnO: 3.2%) normally priced at 35,800 JPY, Zimbabwean Euclase, and more! 《Bulk purchase discounts available》
Sold out [On Sale 5/30 at 10 PM] "Limited 9 Stones" Blue Gem Gacha 💎 Brazilian Paraiba Tourmaline (CuO: 2.2%, MnO: 3.5%), Top Color Benitoite, Hauyne, Apatite (Multi-purchase discount available)

[On Sale 5/30 at 10 PM] "Limited 9 Stones" Blue Gem Gacha 💎 Brazilian Paraiba Tourmaline (CuO: 2.2%, MnO: 3.5%), Top Color Benitoite, Hauyne, Apatite (Multi-purchase discount available)
Sold out Limited to 4 stones: Carving Gacha (pink tourmaline, average 3.4 carats) 1 loose stone (multiple purchase discounts available)

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]

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》

《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

[On sale May 5th at 10 PM JST] Brazilian Indicolite Tourmaline 0.105ct Loose Stone with Appraisal Report
Sold out Brazilian Paraiba Tourmaline (cabochon cut, approximately 2.2mm) 1 loose stone (multiple purchase discounts available)

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)

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)

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

Mexican Cantera Opal 6.112ct Loose
Sold out Limited to 2 stones: 1 Australian opal loose stone (pear cut) Multiple purchase discounts available

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

Paraiba tourmaline from Brazil 4.1mm/0.240ct loose

Sold out オーストラリア産ボルダーオパール 52.582ctルース

Australian boulder opal 52.582ct loose

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

[Dandelion cut] Fire opal 7mm loose

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

1 heat-treated Ethiopian opal (includes a sheet to distinguish it from black opal)

Sold out メキシコ産エッグインオパール 3.054ctルース

[Available from 10 p.m. on July 17th] Mexican egg-in-opal, 3.054 ct. loose stone
Sold out オーストラリア産ブラックオパール 0.894ctルース

【Sale starts at 10 PM on July 20th】Australian Black Opal 0.894ct Loose Stone
Sold out オーストラリア産ブラックオパール 0.766ctルース

[On Sale July 20th at 10 PM] Australian Black Opal 0.766ct Loose Stone
Sold out オーストラリア産ブラックオパール 0.877ctルース

[On sale July 11th at 10 PM] Australian black opal, 0.877ct loose stone
Sold out Pt900ブラックオパール 3.17ct・ダイヤモンド0.105ctペンダントトップ（ネックレストップ） 鑑別書

[Listed in 22602653] [Colorflee] Black Opal 3.17ct Pendant Top (Necklace Top)
Sold out ブラジル産パライバトルマリン 0.056ctルース

Paraiba tourmaline from Brazil 0.056ct loose

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

Limited to 10 stones: Brazilian Bicolor Tourmaline (Baguette Cut) - 1 loose stone. Discounts available for multiple purchases.
Sold out ブラジル産バイカラーパライバトルマリン 0.190ctルース

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

Sold out Pt950 ブラジル産パライバトルマリン 0.043ct リング

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

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

Unheated Brazilian Paraiba Tourmaline 0.088ct loose stone (CuO: 1.9%, MnO: 2.3%)
Sold out メキシコ産オパール 0.677ctルース

Mexican Opal 0.677ct Loose

Sold out 【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

Sold out ブラジル産ピンクトルマリン 0.470ctルース

Brazilian Pink Tourmaline 0.470ct Loose Stone
Sold out ルベライト 0.410ctルース

Mozambique Rubellite 0.410ct Loose Stone
Sold out ブルーウォーターメロントルマリン 2.380ctルース

[On Sale June 6th at 10 PM] Afghanistan Blue Watermelon Tourmaline 2.380ct Loose Stone
Sold out Mexican Hyalite Opal 1.215ct Loose (Faceted Cut)

Mexican Hyalite Opal 1.215ct Loose (Faceted Cut)
Sold out ブラジル産シーフォームトルマリン 0.347ctルース

[Sale on 6/6 at 10 PM JST] Brazilian Seafoam Tourmaline 0.347 ct Loose Gemstone
Sold out オパール 0.878ctルース

Ethiopian Opal 5.7mm/0.878ct Loose (Sphere)

Sold out モザンビーク産エルバイトトルマリン 1.793ctルース

Mozambique Elbaite Tourmaline 1.793ct Loose Stone

Sold out ブラジル産バイカラートルマリン 3.785ctルース

Brazilian Bi-Color Tourmaline 3.785ct Loose Stone [On sale May 27th, 10 PM JST]
Sold out メキシコ産オパール 1.666ctルース

Mexican Opal 1.666ct Loose
Sold out ブラジル産パライバトルマリン 0.036ctルース

[On sale May 17th at 10 PM JST] Brazilian Paraiba Tourmaline 0.036ct Loose Stone (CuO: 1.6%, MnO: 3.1%)
Sold out [On sale May 17th, 10 PM] Brazilian Paraiba Tourmaline 0.035ct Loose Stone (CuO: 2.4%, MnO: 2.5%)

[On sale May 17th, 10 PM] Brazilian Paraiba Tourmaline 0.035ct Loose Stone (CuO: 2.4%, MnO: 2.5%)
Sold out Pink tourmaline 0.795ct loose

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

【Sale starts 5/26 at 10 PM JST】[Colorful] Pt900 Paraiba Tourmaline from Brazil 0.11ct / Diamond 0.58ct Ring (CuO: 2.4%, MnO: 0.9%)

Sold out オーストラリア産ブラックオパール 0.522ctルース

[On sale May 24th at 10 PM] Australian Black Opal 0.522ct Loose Stone

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》

【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

Brazilian Paraiba Tourmaline 0.177ct loose stone (CuO: 2.1%, MnO: 1.3%)
Sold out モザンビーク産パライバトルマリン 1.581ctルース

Paraiba tourmaline from Mozambique 1.581ct loose stone (CuO: 0.5%, MnO: 1.0%)
Sold out ブラジル産パライバトルマリン 0.216ctルース

Brazilian Paraiba Tourmaline 0.216ct loose stone (CuO:1.2%, MnO:2.7%)
Sold out エチオピア産ハニカムオパール 3.566ctルース

Ethiopian honeycomb opal 3.566ct loose stone

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.