















【Available 9/6 at 10 PM】 Tanzanian Windsor Sapphire (Purple Sapphire) 0.277ct Loose Gemstone
Sapphire is a world-famous gemstone that needs no introduction. Mineralogically, it is the same as ruby—corundum—but all corundum that is not red is called sapphire. It is known for its diverse color variations, including blue, pink, yellow, and green. This is a sapphire from Windsor, Tanzania. Windsor sapphires are not widely circulated in the market and are known among gem collectors as a specific locality. Tanzania is recognized as one of the world's leading gemstone-producing regions, yielding many beautiful stones such as spinel and tanzanite, and it also produces attractive sapphire crystals.
・Type: Loose stone (Natural)
・Stone name: Windsor Sapphire from Tanzania
・Weight: 0.277ct
・Size: 3.3×3.3mm
・Shape: Asscher cut
・Condition (Scratches/Chips): S
・Inclusions: None
・Remarks: Usually, this stone has been heat-treated.
*While sapphires are generally heat-treated, this particular item did not yield a definitive conclusion regarding heating during standard microscopic examination. Determining whether a stone is heated or unheated requires advanced analysis by a gemstone identification laboratory.
・Accessories: KARATZ quality guarantee, loose stone case (or a clear zip-top bag if the stone does not fit)
▷ Jewelry Customization Available
If you would like to have this stone made into a piece of jewelry, please order it along with your preferred setting from the link below.
・Simple Order [Choose from Stone]
・Semi-Order [Choose from Stone]
*If you would like an image of the stone placed in a setting, wish to consult about a full custom order, or have any other questions, please feel free to contact us here.
*Rough stones cannot be processed. Some stones may also be ineligible for customization.
※ We strive to ensure that the photos represent the true colors of the actual product, but the appearance may differ slightly depending on the lighting conditions during photography or your monitor settings. Additionally, some photos may be taken using a penlight.
※ For products featuring UV fluorescence photos, these are taken using a 365nm wavelength blacklight. If you use a light with a different wavelength (e.g., around 395nm), the fluorescence may appear weaker or be difficult to observe. The blacklight used by our store can be found here.
※ Please refer to here for information regarding scratches, chips, treatments, and inclusions.
※ For other frequently asked questions, please refer to here.
karatz_item_id: 12564142
・Type: Loose stone (Natural)
・Stone name: Windsor Sapphire from Tanzania
・Weight: 0.277ct
・Size: 3.3×3.3mm
・Shape: Asscher cut
・Condition (Scratches/Chips): S
・Inclusions: None
・Remarks: Usually, this stone has been heat-treated.
*While sapphires are generally heat-treated, this particular item did not yield a definitive conclusion regarding heating during standard microscopic examination. Determining whether a stone is heated or unheated requires advanced analysis by a gemstone identification laboratory.
・Accessories: KARATZ quality guarantee, loose stone case (or a clear zip-top bag if the stone does not fit)
▷ Jewelry Customization Available
If you would like to have this stone made into a piece of jewelry, please order it along with your preferred setting from the link below.
・Simple Order [Choose from Stone]
・Semi-Order [Choose from Stone]
*If you would like an image of the stone placed in a setting, wish to consult about a full custom order, or have any other questions, please feel free to contact us here.
*Rough stones cannot be processed. Some stones may also be ineligible for customization.
※ We strive to ensure that the photos represent the true colors of the actual product, but the appearance may differ slightly depending on the lighting conditions during photography or your monitor settings. Additionally, some photos may be taken using a penlight.
※ For products featuring UV fluorescence photos, these are taken using a 365nm wavelength blacklight. If you use a light with a different wavelength (e.g., around 395nm), the fluorescence may appear weaker or be difficult to observe. The blacklight used by our store can be found here.
※ Please refer to here for information regarding scratches, chips, treatments, and inclusions.
※ For other frequently asked questions, please refer to here.
karatz_item_id: 12564142
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【Available 9/6 at 10 PM】 Tanzanian Windsor Sapphire (Purple Sapphire) 0.277ct Loose Gemstone
Sale price¥12,800
Regular price




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