I must admit I have not been following it much but typically it seems most governments want about 30% of the total. This is way beyond that.

If they wanted to give it to the Chinese they could have just pulled a crystallex.
http://www.mining.com/crystallexs-las-cristinas-project-is-unilaterally-terminated/

I kind of get the feeling that they are just trying to milk as much out of it as they can and are driving a real hard bargain.