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

Fire Opal (Common Opal) 2 stone set《Discount available for multiple purchases》 Sale price¥3,980

Additional charge: K18WG (base metal) + 10,000 yen Sale price¥18,800
Limited to 8 stones: Ethiopian black opal (heat-treated, identification instructions included, average 2ct, approx. 11x8mm) 1 loose stone (multiple purchase discounts available)

Limited to 8 stones: Ethiopian black opal (heat-treated, identification instructions included, average 2ct, approx. 11x8mm) 1 loose stone (multiple purchase discounts available) Sale price¥8,800
[Limited to 6 stones] [Mr. Sanjay] Mexican opal or Sri Lankan spinel 1 loose stone (with defects) [Multiple purchase discount available]

[Limited to 6 stones] [Mr. Sanjay] Mexican opal or Sri Lankan spinel 1 loose stone (with defects) [Multiple purchase discount available] Sale price¥3,980
《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》 Sale price¥3,980
[Option] Paraiba tourmaline analysis report attached identification certificate issuance fee

[Option] Paraiba tourmaline analysis report attached identification certificate issuance fee Sale price¥15,000
Opaque stone gacha💎《2 stones remaining》Dunilite, thulite, green opal with date stamp, etc. (Plus, you'll get 1 Hokkaido rhodochrosite stone)《Multiple purchase discounts available》

Opaque stone gacha💎《2 stones remaining》Dunilite, thulite, green opal with date stamp, etc. (Plus, you'll get 1 Hokkaido rhodochrosite stone)《Multiple purchase discounts available》 Sale price¥5,980
Limited to 12 stones Tanzanian Milky Opal Cat's Eye (7.5 x 5.5 mm) Multiple purchase discounts available

Limited to 12 stones Tanzanian Milky Opal Cat's Eye (7.5 x 5.5 mm) Multiple purchase discounts available Sale price¥3,980
ブラジル産パライバトルマリンリング・ハーフエタニティリングセット（1.2mm）

Brazilian Paraiba Tourmaline Ring and Half Eternity Ring Set (1.2mm) Sale price¥188,000
Limited to 23 stones: 1 Ethiopian opal loose stone (sphere, 4.5-5.0mm) Multiple purchase discounts available

Limited to 23 stones: 1 Ethiopian opal loose stone (sphere, 4.5-5.0mm) Multiple purchase discounts available Sale price¥5,980
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] Sale price¥2,980
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 Sale price¥14,800
ブラジル産パライバトルマリン 0.254ctルース

Paraiba tourmaline from Brazil 0.254ct loose Sale price¥16,800
Mexican Hyalite Opal 2.592ct loose

Mexican Hyalite Opal 2.592ct loose Sale price¥9,800
カンテラオパール 5.750ctルース

Cantera Opal 5.750ct loose Sale price¥19,800
マルチカラートルマリン 1石（オクタゴナルカット,八角形,5mm） - KARATZ STORE｜カラッツSTORE

Multi-colored tourmaline 1 stone (octagonal cut, octagonal, 5mm)《Multiple purchase discount available》 Sale price¥3,980
非加熱ブラジル産パライバトルマリン 0.065ctルース（CuO:2.0%、MnO:2.2%）

[On sale 3/2 at 10pm] Unheated Brazilian Paraiba Tourmaline 0.065ct loose stone (CuO: 2.0%, MnO: 2.2%) Sale price¥59,800
モザンビーク産エルバイトトルマリン 1.580ctルース（CuO:0.1%,Mn0:1.9％）

[On sale 3/2 at 22:00] Elbaite tourmaline from Mozambique 1.580ct loose stone (CuO: 0.1%, Mn0: 1.9%) Sale price¥59,800
アフガニスタン産バイカラートルマリン 2.664ctルース（シーフォームトルマリン）

[On sale at 22:00 on 3/9] 2.664ct bicolor tourmaline loose stone from Afghanistan (seafoam tourmaline) Sale price¥128,000
ブラジル産グリーントルマリン 1.031ctルース

[On sale 3/1 at 22:00] Brazilian green tourmaline 1.031ct loose stone Sale price¥22,800
ブラジル産ピンクトルマリン 0.772ctルース

[On sale at 10pm on 2/26] Brazilian pink tourmaline 0.772ct loose stone Sale price¥12,800
非加熱ブラジル産パライバトルマリン 0.070ctルース（CuO:1.9%、MnO:2.2%）

[On sale from 10pm on 2/26] Unheated Brazilian Paraiba Tourmaline 0.070ct loose stone (CuO: 1.9%, MnO: 2.2%) Sale price¥55,800
ブラジル産パライバトルマリンインクォーツ 0.295ctルース

[On sale at 22:00 on 2/15] Brazilian Paraiba Tourmaline in Quartz 0.295ct loose stone Sale price¥14,800
バイカラートルマリン 0.891ctルース

[On sale from 10pm on 2/21] Brazilian bicolor tourmaline 0.891ct loose stone Sale price¥9,800
アフガニスタン産バイカラートルマリン 0.672ctルース

[On sale at 22:00 on 2/9] Afghanistan bicolor tourmaline 0.672ct loose stone Sale price¥9,800
アフガニスタン産バイカラートルマリン 0.471ctルース

[On sale at 22:00 on 2/9] Afghanistan bicolor tourmaline 0.471ct loose stone Sale price¥9,800
アフガニスタン産バイカラートルマリン 0.673ctルース

[E_27 Yurakucho Marui take-out] [On sale from 22:00 on 2/9] Afghanistan bicolor tourmaline 0.673ct loose Sale price¥15,800
ホンジュラスオパール 0.999ctルース

[On sale at 22:00 on 2/9] Honduran Opal 0.999ct Loose Sale price¥9,800
ホンジュラスオパール 1.124ctルース

[On sale at 22:00 on 2/9] Honduran Opal 1.124ct Loose Sale price¥7,980
ブラジル産インディゴライトトルマリンインクォーツ 1.626ctルース

[On sale at 22:00 on 2/10] Brazilian indigolite tourmaline in quartz 1.626ct loose stone Sale price¥12,800
ブラジル産インディゴライトトルマリンインクォーツ 2.036ctルース

[On sale at 22:00 on 2/10] Brazilian indigolite tourmaline in quartz 2.036ct loose stone Sale price¥12,800
[On sale from 22:00 on 2/2] [Limited to 4 stones] Mexican Cantera Opal 1 loose stone (10 x 8 cm) [Multiple purchase discounts available]

[On sale from 22:00 on 2/2] [Limited to 4 stones] Mexican Cantera Opal 1 loose stone (10 x 8 cm) [Multiple purchase discounts available] Sale price¥4,980
メキシコ産カンテラオパール 5.126ctルース

[On sale 2/2 at 10pm] Mexican Cantera Opal 5.126ct loose stone Sale price¥25,800
メキシコ産カンテラオパール 7.081ctルース

[On sale 2/1 at 22:00] Mexican Cantera Opal 7.081ct Loose Sale price¥15,800
メキシコ産カンテラオパール 4.602ctルース

[On sale 2/1 at 22:00] Mexican Cantera Opal 4.602ct loose stone Sale price¥29,800
メキシコ産カンテラオパール 6.385ctルース

[On sale 2/1 at 22:00] Mexican Cantera Opal 6.385ct loose stone Sale price¥18,800
メキシコ産カンテラオパール 1.842ctルース

[On sale 2/1 at 22:00] Mexican Cantera Opal 1.842ct loose stone Sale price¥39,800
メキシコ産カンテラオパール 4.300ctルース

[On sale 2/6 at 22:00] Mexican Cantera Opal 4.300ct Loose Sale price¥69,800
メキシコ産カンテラオパール 9.909ctルース

[On sale at 22:00 on 2/6] Mexican Cantera Opal 9.909ct loose stone Sale price¥39,800
メキシコ産カンテラオパール 5.238ctルース

[On sale 2/6 at 22:00] Mexican Cantera Opal 5.238ct loose stone Sale price¥15,800
メキシコ産カンテラオパール 7.275ctルース

[On sale 2/8 at 10pm] Mexican Cantera Opal 7.275ct loose stone Sale price¥35,800
メキシコ産カンテラオパール 5.261ctルース

[On sale 2/8 at 10pm] Mexican Cantera Opal 5.261ct loose stone Sale price¥49,800
オーストラリア産ブラックオパール 0.856ctルース

[On sale 2/1 at 22:00] Australian black opal 0.856ct loose Sale price¥12,800
オーストラリア産ブラックオパール 1.018ctルース

[On sale 2/1 at 22:00] Australian black opal 1.018ct loose Sale price¥18,800
オーストラリア産ブラックオパール 0.812ctルース

[On sale 2/4 at 10pm] Australian black opal 0.812ct loose Sale price¥8,800
ブラジル産インディゴライトトルマリン 1.060ctルース

[On sale at 22:00 on 2/5] Brazilian indigolite tourmaline 1.060ct loose stone Sale price¥19,800
ピンクトルマリン 0.333ctルース

Pink tourmaline 0.333ct loose stone Sale price¥9,800
メキシコ産ファイアオパール 0.343ctルース

Mexican Fire Opal 0.343ct Loose Sale price¥15,800

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.

The fifth reprint has been decided and is now on sale at bookstores nationwide and online.

Written by KARATZ, book “Jewelry Illustrated Book”

The book provides explanations about over 300 types of gemstones, from new standard birthstones to rare stones that are hard to find, as well as a diary of our company representative, Mr. Koyama's, gemstone shopping experience in Thailand and Sri Lanka, and tips for photographing gemstones, allowing you to learn about the appeal of gemstones from various perspectives.

KARATZ・Five Commitments