I saw a video about this a few months ago. It seems to make a lot more sense than burying a cement box in the ground or burning the body. It’s possible the the sources I’ve run into so far are bias, but I can’t really see any downsides.
> Bones are reduced to a fine powder by equipment after the soil is removed from the Recompose vessel. Staff also screen for non-organics such as implants, which are recycled whenever possible. The reduced bone is added back to the compost to help balance the compost nutrients and make minerals available to plants. It continues to break down and return to the environment over time. Recompose follows all compost-testing regulations put forth by the Washington State Department of Licensing and the Board of Health.