I can't do the effect shown in the picture, please help!

help.3dm (9.5 MB)

I want to create lines on the surface like the one holding the gem on the picture
but its curvature makes it very difficult for me to figure out how to do it, please help.

Hello- something like this, I would say, to get the basic surface, then add the details.

Help_Maybe.3dm (453.1 KB)
@maimun2002 V6 file here now.


Thanks for the answer, but I have Rhino 6 and the file won’t open.
Can you resend it?
Thanks in advance!