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boulder opal

Boulder opal is an opal with sandstone or iron ore as its host rock, and it exhibits a play of color effect. The main production area is Queensland, Australia. Because it is often cut into unique shapes, it is a gemstone that can be enjoyed in many different ways. Opal is the birthstone for October.

Karatz GemMagazine
" Boulder Opal "

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Boulder opal 1.640ct loose Sale price¥19,800

Boulder opal 41.770ct loose Sale price¥39,800

Boulder opal 17.450ct loose Sale price¥29,800

Boulder opal 15.020ct loose Sale price¥29,800

Boulder opal 12.220ct loose Sale price¥19,800

Boulder opal 6.160ct loose Sale price¥25,800

Boulder opal 4.980ct loose Sale price¥29,800

Boulder opal 4.720ct loose Sale price¥29,800

Boulder opal 7.680ct loose Sale price¥29,800

Sold out 【大人用】宝石磨きに挑戦してみよう「自分で出来る原石磨きセット」(初心者向け:バイカラーフローライト)・ボルダーオパール付※原石磨きコンテスト対象 ※
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 Limited to 5 stones: 1 loose Australian boulder opal (average 12.5ct) Multiple purchase discounts available
Sold out オーストラリア産ボルダーオパール 3.140ctルース
Sold out オーストラリア産ボルダーオパール 2.140ctルース
Sold out オーストラリア産ボルダーオパール 2.890ctルース
Sold out オーストラリア産ボルダーオパール 2.970ctルース
Sold out オーストラリア産ボルダーオパール 2.400ctルース
Sold out オーストラリア産ボルダーオパール 1.850ctルース
Sold out オーストラリア産ボルダーオパール 1.303ctルース
Sold out オーストラリア産ボルダーオパール 1.615ctルース
Sold out オーストラリア産ボルダーオパール 1.903ctルース
Sold out オーストラリア産ボルダーオパール 3.489ct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.

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.