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• 純銀は99.9% 純銀と定義されていますが、ほとんどの用途には柔らかすぎます。

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• 夢と願望とは何ですか？

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• Opal is particularly famous because of its very diverse shapes and forms.
• The formation of opal is a completely natural but long process.
• The substance itself is actually a solution of water and silica.