What exactly are they used for?
how do you get them?
Are they basically "Bonus" items you look with (or instead of) normal fragments? I know they can be used as ~6 fragments by themselves, but what is the exact deal with them?
9/10 pages on archaeology are copy & paste regurgitation of the same information to try and pull in advertising, and are not really in any way useful as some of them still say it's still for the path of the titans (and that's the first page of results for google)
Also, what controls what your next 'project' is? Random?
And when can you start getting 'Rare' projects? (skill level? looting an item (and a required skill level?)?)