After having done a fair share og digging, I figured I would share a tip of mine, that will greatly increase your speed and chance to find fragments faster. Once you master this, you'll be solving shit like there's no tomorrow... Maybe not, but it is faster!
I've not seen it posted already, which is a little surprising since this will be common sense to many, we'll see how you like it. There's no reason to flame the shit out of me if you found this method yourself.
The images below should explain everything, take a look:
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And a mockup, without an archaeology site:
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Doing this will allow you to find the fragment with only 2 digs once you reach a green marker, instead of fondling around in the sand like a mole. I know all too well from experience that even a green marker can be further away than you think, but doing it this way will allow you to pinpoint the exact location every time. Well, almost. You will find that even the green markers aren't 100% accurate, but it sure does improve things.
Also remember that with archaeology, lightning does strike twice, or even thrice. I have had 3 fragments right on top of each other before.
Hope you like the tip, and that you are able to further your archaeology skills a little with it. I was going to make a movie, but I just can't be arsed. I doubt it's necessary either, but let me know if it is.
PS. Please ignore typos in the images, was thrown together a little quick.