This plugin allows you to compress coal blocks into a diamond using a piston. Will not work if the piston is otherwise unable to function (e.g. obsidian in the path)
This resource is part of my custom series. You can view the full list here, prefixed by [Custom]. This series comprises of custom requests from server owners, where I help them out for free and in exchange, I keep all rights to the resource. I am releasing them here for any other server owners who can find a use for them.