Recently I've noticed a new resource griefer came through. Ok whatever it happens; but it made me think about boulders in-game as a resource, and their output. I think you shouldn't make Runestones and Querns straight from the natural boulders, but have to quarry a "cellar stone" liftable boulder first.
Quarry Stone action
Basically instead of using the Runestone and Quern build action on a natural boulder, have them only work on those cellar stones. To make them accessible before hard metal/cellars, allow them to be quarried from natural boulders individually (similar to building a cellar). Perhaps a boulder will hold 4 of these stones, or maybe 9 (since boulders are basically 3x3 tiles large). Once the cellar stones have been quarried then the boulder disappears like normal.
This will help slow down resource griefers, plus make runestones less wasteful of a communication method, and give pre-metal hearthlings access to cellar stones, which are useful for traps and pens and other things.

Runestone replies/editing/clearing
It would be nice if you can add new tags to Runestones that were already placed; perhaps a reply, or an addendum, or information update. This should of course require time and energy; perhaps you can drop a dream on a written Runestone and then the next view/activation of the Runestone is a message box to add a reply. Or a new chemical mixture of rustroot, sand, and a dream in a clay jar to make a stone-scrubbing solvent or something, to erase a troll rune. These aren't that well thought out I'll admit and can be used to grief legitimate runestones, but just some general concepts to do more with the Runestones in-game.
Storage structures, religious sites
Another thing I've been thinking about is outdoor storage structures; I know there's several threads of this sort of thing, some I've gotten ideas from. I was thinking of making two seperate threads to put these in, but since they will be stone related I figured to post them in this thread.
Stone Cairn
I really don't see why nomadic Hearthlings can not build stone cairns anyway; they were often used in the wilderness for emergency supplies, or hunting equipment, and other uses. A static 1 tile sized structure that takes 30-50 stones to build, and maybe Bone Glue and/or a piece of Dried Hide, and acts as a storage container (maybe 5x5 or 6x6). Resistant to decay, but can be destroyed -- maybe similar to a Hearthfire or a little weaker. I think this would be useful, as you could do things like have hidden treasure; or just leave maps of the local area in them, or a cache of bricks out along your farther walls.

There are plenty of other variations, make them work like lean-tos or a combination storage like a wagon; but I think a small simple one would be the best. But thinking about this, I thought about a storage plot for another particular item: corpses! So that got me thinking about the under-use of stone in the Hearthland's religious aspects!
Burial Cairn
Pretty self explanatory. Stones, soil, dreams, builds a 1 tile sized container structure that only accepts hearthling skeletons (a single skeleton). Optional features would be if a hearthling right clicks they read the inscription of the hearthling that rests there. Or perhaps an inscription like a runestone where the grave builder writes an inscription. You could also add this to the Ancestor Worship system, and make it so gravesites act as shrines with a numen bonus; or maybe a special bonus for a direct ancestor's burial site. Sort of like alternate shrines.
Burial Mound
This would be similar to a grave, except it would be a larger structure (like 3x3 tiles) with more container slots. Perhaps it can be a combination container like the Wagon, and have slots to store skeletons, and a spot to store random items. These could signify someone's possessions, or treasure; you can make it like a tomb for a lost Chieftain or anything like that. Perhaps make it so it's open with 6 slots for skeletons, and when the last one is full, or a cellar stone is dropped in, the mound becomes sealed and the only interaction would be reading the inscription. I'm not experienced with the mechanics of crime, but having grave robbing in those places an option I suppose as well.
With both the grave and larger burial mound, I think that any demolition or vandalism should leave vandalism scents regardless of ownership (as they belong to the venerable ancestors now).

Stone Shrine
Basically a static shrine made of stone, dreams, and bones, which gives a minor numen bonus compared to the standard shrine. However if burial sites were made to act as specialized shrines, then this structure would be redundant.
That's it for now, and covers my main ideas, although others I have which have been discussed enough are things like grain silos, garden walls, and stone cottages; so I won't go into them in this thread.
Thanks for reading!
