喜闻乐见

。。。

据说6N还是多少以上能成为白色？

看网上的视频都是金黄色的，挺漂亮

纯度问题？？！

纯度问题吧

因为它们玻封在稀有气体中

纯度越高金黄色越浅

我记得课本上写的也是略带金黄色。

首先请相信我，恕我直言，任何资料说铯是银白色的编写者都是没有看过铯的
我见过不下几十个铯的实物样本和照片，无一例外全部都是金黄色，无非略微的颜色差距而已。
对于这个话题有国外有人研究过：https://w【】ww.cs.roch【】ester.edu/~nelson/cesium/ces【】ium_color.html
--Reference goes on to explain the color in terms of the band structure of the metals, the salient point being that for higher atomic numbers, overlap of the s with the d orbitals makes a more significant contribution to the band structure, generally lowering the energy required for exitation of conduction band electrons, until in the case of cesium there is significant absorbtion in the blue region of the spectrum producing the golden color.
至于这里所谓的reference，我并没有找到，不过wiki上也有类似的说法：The golden colour of caesium comes from the decreasing frequency of light required to excite electrons of the alkali metals as the group is descended. For lithium through rubidium this frequency is in the ultraviolet, but for caesium it enters the blue–violet end of the spectrum; in other words, the plasmonic frequency of the alkali metals becomes lower from lithium to caesium. Thus caesium transmits and partially absorbs violet light preferentially while other colours (having lower frequency) are reflected; hence it appears yellowish.
这段文字的来源参考：Addison, C. C. (1984). The chemistry of the liquid alkali metals. Wiley. p. 7. ISBN 9780471905080.
然后《乌尔曼工业化学大全》和格林伍德都都描述铯是金黄色的，所以结论是什么就不用多说了吧。顺便补一张我的铯的样本，虽然不全，但也就是这么回事

新制的是白色，网上有视频

就是金黄色

首先需要说明纯度和铯的色泽并没有关系，onyx以前有卖过原子钟级的5N铯，颜色与4N的几乎没有区别。但是要说明一点就是当铯被轻微氧化后会由于溶解黑色的复杂氧化物过氧化物等加深颜色直至彻底覆盖氧化物变黑，但onyx的铯从来都是在氩气下的，与真空玻封（如alfa的breakseal铯）的色泽并无区别。。最有可能的原因是光线，在一些比较暗的环境下铯看起来就会比较接近银色，毕竟铯本来色泽就不重