Adds a Rocky Diet

Taking the ore eater trait, you only gain nutrition from ore.
The amount varies, mainly based on the rarity/quality of what you're eating.

5 raw diamonds or verdantium will feed you well, while it'll take a handful of hematite or carbon to do the job. Better stick to the good stuff - it's in your best interest!

code/modules/mining/ore.dm

@@ -121,4 +121,12 @@
 		var/obj/item/device/core_sampler/C = W
 		C.sample_item(src, user)
 	else
-		return ..()
+		return ..()
+
+/obj/item/weapon/ore/attack(mob/living/M as mob, mob/living/user as mob)
+	if(ishuman(M))
+		var/mob/living/carbon/human/H = M
+		if(H.species.eat_ore == 1)
+			H.eat_ore(src)
+			return
+	..()