These are nail covers made of gold. It was very common for the Manchu elite of the Qing Dynasty to wear them, so you can say it's a Manchu tradition (the Qing emperors were Manchu). But I can't remember the Chinese name of these covers, I'll edit when I'll find out ...

edit: Perhaps I might add the reason to these nail protections. Long nails made manual labour impossible, hence the Manchu elite usually had, at least, one very long fingernail to show that they didn't engage in manual labour (and consequently show their social status). The problem being long fingernails can break easily ... So they (only women used them though) needed nail protectors to protect their long nails. If you want a good source about clothes of the Qing Dynasty : Chinese dress, from the Qing Dynasty to the present by Valery M. Garett is quite good in my opinion.

edit 2: http://books.google.fr/books/about/Chinese_Dress.html?id=oipliT_dA4kC&redir_esc=y Turns out the book is available freely on google books. It speaks about fingernails on page 54.