After polishing, each Go stone is sorted
by our quality staff. In our sorting process, we carefully inspect the shape,
crack, pure white color and texture using our "Master
Stones". (At this stage, approx. 20 % of stones is judged unsuitable.)
>>What is a "Master Stone"? |
Snow grade(YU-KI) |
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| 80% of surface has beautiful
very fine stripes all over. |
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Snow Grade Stone has white shine luster and very fine elegant stripes, which is the characteristic of clamshells. Its exquisite shape is practical and at the same time very artistic, capturing the player's heart. (Approx. 10 % of total production) |
Moon grade(TSU-KI) |
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| Less stripes than Snow grade, but 70% of surface has fine stripes. |
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Moon Grade Stone has faint stripes with some space in between.
Its two-tone color make a beautiful contrast as if representing player's strong
will for victory. (Approx. 30 % of total production) |
Standard grade(JI-TSU-YO) |
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| 7 to 8 wide stripes can be seen on surface. The number of strips, not the beauty of stripes, is a key factor to determine these grades. |
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Standard stone has wide stripes. Like two other grades, it has nice smooth texture and beautiful roundness. (Approx. 40 % of total production) |
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