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1·In fact, it became so valuable that it was known as white gold and spies were sent to China to discover what they did to the clay to produce such high-quality merchandise.

事实上，它变得如此珍贵，以至于被称为“白金”，间谍被派往中国，以查明他们如何处理粘土，从而生产出如此高质量的商品。