Cobalt ores found in China have a high manganese content, which produces a more muted blue-gray color.
中国发现的钴矿含锰量高，因此呈现出较弱的蓝灰色。
2
From the Middle East the Chinese acquired a blue pigment—a purified form of cobalt oxide unobtainable at that time in China—that contained only a low level of manganese.
中国人从中东获得了一种蓝色颜料，这是一种当时在中国很难得到的纯净的氧化钴，这种颜料只含有少量的锰。
3
The peak cobalt rodlet temperature doesn't exceed the cobalt melt temperature during these two cases.