Don’t write angry emails. There at least two very solid reasons for this.
First, it’s very difficult to express your emotions and tone in writing, thus your message can be understood and perceived completely different that what you have intended.
Second, delivering a “bad” message face to face allows you to observe their immediate reaction, thus understand whether the person admitted their fault or is inclined to advance the conflict.
If you cannot avoid writing an angry email, don’t start writing it right away. Take 30-60 minutes to do something else, get calm and then write the message in a nice way.