Hello,
I am no expert, but this looks refinished to me. I have seen several ones with similar pattern, coming out of Asia (Japan and HK) with different people claiming ith was the orinal factory finish - which I doubt.
Below is an original watch that I believe, have aged to result in such effect:
![Image](https://www.romainrea.com/wp-content/uploads/2019/06/p_5_6_6_2_5662-JAEGER-LECOULTRE-MEMOVOX-BLUE-LAPIS-LAZULI-DIAL-1440x1084.jpg)
To compare with my own E875 with the original blue finish:
![Image](https://live.staticflickr.com/65535/51750329434_6d158ccdef.jpg)
Despite those being several yers apart, the colors seem consistent, but not with one you posted earlier - it looks too clean and homogenious to me.