Hello, I’m sorry to have to say this, but it seems you’ve stumbled upon something pretty serious. I took a while to reply because I was checking through the code. To make a long story short, it doesn’t make sense that only some of the keystones would disappear, which is what prompted my lengthy checking.

In short, when I originally tested the system (prior to archaeology coming out) to make sure it patched properly, I only pickup artifacts from the first couple of categories in the list. If you do this the data will patch normally, or at least you won’t see the error due to their placement in the array. Upon investigation earlier today, I found that the data was corrupting itself about 3/4 of the way through recording. Essentially the last two categories weren’t recording properly. In most cases something like this would be salvageable, this however is not.

What I am unfortunately going to have to do is a universal reset on archaeology. I hate to do it since I’m sure people will be losing progress, but there isn’t a way to recover the data as the latter part of it was never recorded properly in the first place.

What resetting will do is make all the keystones appear in the world again. I’m currently looking into dropping a chest full of fragments into the world to hopefully alleviate some of the pain of having to redo stuff again. I apologize for this, I try to make sure that any systems added to the game work, or can at least be fixed without loss of data. However as a one person dev team things can slip through the cracks. In any case, thanks for reporting this, the fix will be implemented on Friday with the next patch. Until then I’d recommend not touching archaeology.