I understand that Tim is dealing with a lot of bones, but just to add a few comments here for the other "regular folk" like myself, there is no need to make this too complicated. Like most of us, I suspect, I have waaaaaaay to much to do to be spending my time and/or money grinding, cooking, charring, pulverizing, etc. bones that are going into the dirt to feed my veggies.
(1) Regardless of where you live, you CAN compost both meat and bones....provided you (a) keep the critters/dogs/racoons/rats/etc. from getting to them and (b) keep your ratio of bones to compost/wood chips reasonable; e.g., if you are composting an entire animal(s) [Salatin], you're going to need a lot of wood chips. If you're composting a pot full of chicken bones [after making stock
] once a week, you can dump into regular ole compost. I don't have rats - just dogs/cats/coons, so I just need to bury the meat/bones a few inches in the compost and cover my compost with wire mesh weighed down with bricks. If you have rats, you'll need to be more aggressive in your [metallic] protection because I think they will be happy to chew through, burrow, or do whatever is necessary to get to it. FYI I have been composting meat, bones, fat, used cooking oil, etc. for decades here in the burbs. My primary frustration these days is that BSF larvae will eat most of my compost and crawl away with the nutrients and organic material which I would prefer to end up in the dirt; I can fix that by making a BSF bin, capturing the larvae, and feeding them to chickens (but that's a different thread).
(2) As one of the other posters referenced, after a few months in a compost pile, animals will have no interest in the bones. The surface [and sub-surface] of my garden is littered with bones and pieces of bones. They break down very slowly, but WHO CARES??? (at least I don't). I like to think of them as a system of 10-year slow-release of calcium and other nutrients.
