now with 100% less snowflake

code/game/objects/items/stacks/sheets/mineral.dm

@@ -220,6 +220,7 @@ var/global/list/datum/stack_recipe/abductor_recipes = list ( \
 	origin_tech = "materials=4"
 	sheettype = "tranquillite"
 	materials = list(MAT_TRANQUILLITE=MINERAL_MATERIAL_AMOUNT)
+	wall_allowed = FALSE	//no tranquilite walls in code
 
 /obj/item/stack/sheet/mineral/tranquillite/New(loc, amount=null)
 	..()

code/game/objects/items/stacks/sheets/sheets.dm

@@ -13,6 +13,7 @@
 	var/full_window = null			//moving the var declaration to here so this can be checked cleaner until someone is willing to make them share a base type properly
 	usesound = 'sound/items/Deconstruct.ogg'
 	toolspeed = 1
+	var/wall_allowed = TRUE	//determines if sheet can be used in wall construction or not.
 
 
 // Since the sheetsnatcher was consolidated into weapon/storage/bag we now use