I found these riddles , can anyone help me figure it out?

[Manwe]

... and here's another one:

I am a diamond,
white and shiny stone,
you can see me,
but never alone,
you can seek me,
but will not find me nigh,
never live,
but will yet die,
what am I?

ps. I'm not sure about the nigh, but I think you see my point anyway.