Scrying Stones

To get to the area with the scrying spots, head down the path from Mezzamere, and make a right at the intersection in the road at (40, 46). Once you reach the scrying spots, the extra action button will appear, allowing you to use the stone; it is not a static item in your inventory.

While in this area, be careful not to attack any of the [npc=148454] or [npc=152445] in the vicinity, as this will aggro the nearest [npc=152426], which are otherwise neutral. And be EXTRA careful not to tread on any of the eggs strewn about, because doing so will earn you the ire of every crustacean in the immediate area! It's best to dismount here, or at least use a more narrow mount, lest you flatfoot over some mega-crab's offspring, and find yourself in a world of pain quicker than you can say "shellfish allergy"

wouldn't it be nice if they would stack

You must go to the blue outlined circles shown on your minimap and use the "Scrying" extra action button that pops up above your action bar. The icon looks like a pink runestone. Once you use that action button it will make the chest pop up in which you can loot. If you don't see the extra action button and you are inside of the blue circle, move your character closer to the center of the circle and it should pop up.

Note: Using the Scrying button is what grants you quest credit, NOT actually looting the chest.