How do I donate diamonds to another member in my alliance?

I have not found anyway to donate your existing diamonds to others. The only option that seems to exist in the game is to buy diamonds with money and place them in a red envelope rewards that others in your alliance can claim in the chat. This is done randomly though to you cannot easily control what they get.

To do this go int the alliance chat option and look for the red envelope icon to the upper right. Here you have the option to buy diamonds and place them in the envelope. You can choose how many people get them (min 3) and they will need to go to state chat to claim them.