钴的

例句：

1. 1.Cobalt is a rare and valuable metal used in jewelry and electronics.
   钴是一种稀有且珍贵的金属，用于珠宝和电子产品。
2. 2. Cobalt is often used as an additive to improve the strength of steel.
   钴常被用作添加剂，以增强钢的强度。
3. 3.The cobalt blue color of the sky is breathtakingly beautiful.
   天空的钴蓝色是如此美丽，令人惊叹。