diff --git a/code/game/objects/items/stacks/sheets/glass.dm b/code/game/objects/items/stacks/sheets/glass.dm
index eedf5f85c1..47c881bbdf 100644
--- a/code/game/objects/items/stacks/sheets/glass.dm
+++ b/code/game/objects/items/stacks/sheets/glass.dm
@@ -19,7 +19,7 @@ GLOBAL_LIST_INIT(glass_recipes, list ( \
 	singular_name = "glass sheet"
 	icon_state = "sheet-glass"
 	item_state = "sheet-glass"
-	materials = list(/datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 50, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/glass
@@ -83,7 +83,7 @@ GLOBAL_LIST_INIT(pglass_recipes, list ( \
 	singular_name = "plasma glass sheet"
 	icon_state = "sheet-pglass"
 	item_state = "sheet-pglass"
-	materials = list(/datum/material/plasma=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_PLASMA=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 75, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/plasmaglass
@@ -134,7 +134,7 @@ GLOBAL_LIST_INIT(reinforced_glass_recipes, list ( \
 	singular_name = "reinforced glass sheet"
 	icon_state = "sheet-rglass"
 	item_state = "sheet-rglass"
-	materials = list(/datum/material/metal=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_METAL=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 70, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/rglass
@@ -177,7 +177,7 @@ GLOBAL_LIST_INIT(prglass_recipes, list ( \
 	singular_name = "reinforced plasma glass sheet"
 	icon_state = "sheet-prglass"
 	item_state = "sheet-prglass"
-	materials = list(/datum/material/plasma=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT, /datum/material/metal = MINERAL_MATERIAL_AMOUNT * 0.5,)
+	materials = list(MAT_PLASMA=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT, MAT_METAL=MINERAL_MATERIAL_AMOUNT * 0.5,)
 	armor = list("melee" = 20, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 80, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/plasmarglass
@@ -198,7 +198,7 @@ GLOBAL_LIST_INIT(titaniumglass_recipes, list(
 	singular_name = "titanium glass sheet"
 	icon_state = "sheet-titaniumglass"
 	item_state = "sheet-titaniumglass"
-	materials = list(/datum/material/titanium=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_TITANIUM=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 80, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/titaniumglass
@@ -217,7 +217,7 @@ GLOBAL_LIST_INIT(plastitaniumglass_recipes, list(
 	singular_name = "plastitanium glass sheet"
 	icon_state = "sheet-plastitaniumglass"
 	item_state = "sheet-plastitaniumglass"
-	materials = list(/datum/material/titanium=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/plasma=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_TITANIUM=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_PLASMA=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 0, "rad" = 0, "fire" = 80, "acid" = 100)
 	resistance_flags = ACID_PROOF
 	merge_type = /obj/item/stack/sheet/plastitaniumglass
@@ -237,7 +237,7 @@ GLOBAL_LIST_INIT(plastitaniumglass_recipes, list(
 	item_state = "shard-glass"
 	lefthand_file = 'icons/mob/inhands/weapons/melee_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/weapons/melee_righthand.dmi'
-	materials = list(/datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	attack_verb = list("stabbed", "slashed", "sliced", "cut")
 	hitsound = 'sound/weapons/bladeslice.ogg'
 	resistance_flags = ACID_PROOF
@@ -336,5 +336,5 @@ GLOBAL_LIST_INIT(plastitaniumglass_recipes, list(
 	force = 6
 	throwforce = 11
 	icon_state = "plasmalarge"
-	materials = list(/datum/material/plasma=MINERAL_MATERIAL_AMOUNT * 0.5, /datum/material/glass=MINERAL_MATERIAL_AMOUNT)
+	materials = list(MAT_PLASMA=MINERAL_MATERIAL_AMOUNT * 0.5, MAT_GLASS=MINERAL_MATERIAL_AMOUNT)
 	icon_prefix = "plasma"
\ No newline at end of file