This... is far from finished. I've been scrolling around the Java Edition Unused Features page and have thought to myself, "Huh, yeah, sure that's cool."
Right now, there is an unused sound that you can get by doing
/playsound unused_features:ambient.forest.birds master @sand the emeralds are rubies. I used the texture of the Ruby Block from Minecraft Earth, and made the ruby ore texture, but used the Minecraft ruby texture. I find it strange that in Minecraft is the ruby texture... shame they didn't announce rubies in Minecraft Live.

NOT WORKING ON THIS ANYMORE, BTW