![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/2026-10-1111.00.09.png?v=1791684034&width=1246)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/collage_827baa06-30d9-414f-b27a-a690b64c2cbf.png?v=1791683949&width=2000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050806_69e93238-9d3d-4505-85d2-757a0daef11b.jpg?v=1791594084&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050808_38a49d26-a433-49be-9a90-15868aece981.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050810_d34221df-2264-4908-8919-b1153f3ef728.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050812_a15a01f2-17ca-4da4-a210-7321a1028991.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050814_cb0951fd-f1eb-4516-bf07-10a01d9eb6e1.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050816_79658488-ed20-44a0-807c-09c46911751b.jpg?v=1791594084&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050818_e9b70b01-5300-45e1-9cca-80b8a6c97e3a.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050820_39c300e6-9b2a-46c0-851f-da950cd9f1ce.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050822.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050824.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050828.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050830.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050832.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050834.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050836.jpg?v=1791594100&width=4000)
[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》
This is a gacha for synthetic cobalt spinel, featuring a beautiful, vivid blue. Natural cobalt spinel is known for its intense blue color caused by cobalt, making it one of the most popular varieties of spinel. This is a synthetic cobalt spinel that recreates that stunning blue. Its appeal lies in the vivid, uniform color unique to lab-grown stones.
It has been newly cut into a hexagonal shape by Sri Lankan lapidary Mr. Sanje. The sharp hexagonal silhouette, combined with intricately placed facets, reflects light and allows you to enjoy a vivid blue sparkle.
Another interesting characteristic of this synthetic cobalt spinel is that it fluoresces a vivid red when exposed to black light (UV light). You can enjoy two different appearances: a beautiful blue under normal light, and red under black light. At approximately 3mm, this is a loose stone with impressive, vivid color and a unique cut. You will receive one of the 7 stones shown in the photo.
【Contents】
・Synthetic cobalt spinel
(Hexagonal cut, polished by Mr. Sanje / approx. 3mm) 1 out of 7 stones total
《This is a multiple-purchase discount eligible item》
You can receive a discount by purchasing multiple items from the multiple-purchase discount section simultaneously. The discount applies to purchasing multiple units of this item, or by purchasing this item together with other eligible multiple-purchase discount items. If you purchase 2 items, you will receive a 1,000 yen discount off the total; purchase 3 items and receive a 1,500 yen discount off the total.

・Stone Type: Synthetic Stone
・Category: Loose stone
・Size: Refer to ruler photo
・Scratches/Chips: -
・Inclusions: -
・Remarks: ---
・Accessories: Case
※You will receive one stone selected from those shown in the photo. Please note that this is a "dealer's choice" item and you cannot choose the specific stone.
※The only accessory included with this product is a case.
※ We strive to ensure that the photos represent the colors of the actual product, but the appearance may vary slightly due to lighting conditions during photography or your monitor settings. Some photos may have been taken using a penlight.
※ Please see here for information regarding scratches, chips, treatments, and inclusions.
※ For other frequently asked questions, please see here.
karatz_item_id:90003462
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![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/2026-10-1111.00.09.png?v=1791684034&width=1246)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/collage_827baa06-30d9-414f-b27a-a690b64c2cbf.png?v=1791683949&width=2000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050806_69e93238-9d3d-4505-85d2-757a0daef11b.jpg?v=1791594084&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050808_38a49d26-a433-49be-9a90-15868aece981.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050810_d34221df-2264-4908-8919-b1153f3ef728.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050812_a15a01f2-17ca-4da4-a210-7321a1028991.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050814_cb0951fd-f1eb-4516-bf07-10a01d9eb6e1.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050816_79658488-ed20-44a0-807c-09c46911751b.jpg?v=1791594084&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050818_e9b70b01-5300-45e1-9cca-80b8a6c97e3a.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050820_39c300e6-9b2a-46c0-851f-da950cd9f1ce.jpg?v=1791594083&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050822.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050824.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050828.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050830.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050832.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050834.jpg?v=1791594100&width=4000)
![[Available 11/1 at 10 PM] 《7 stones limited》 Synthetic Cobalt Spinel (by Mr. Saint-Ger, 3mm hexagonal cut) 《Multi-buy discount available》](http://store.karatz.jp/cdn/shop/files/PA050836.jpg?v=1791594100&width=4000)



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