diff --git a/code/modules/materials/material_sheets.dm b/code/modules/materials/material_sheets.dm
index 82d55960df2..cfe4e1ed474 100644
--- a/code/modules/materials/material_sheets.dm
+++ b/code/modules/materials/material_sheets.dm
@@ -29,7 +29,8 @@
 	desc = "A stack of sheets of [material.display_name]."
 	recipes = material.get_recipes()
 	stacktype = material.stack_type
-	origin_tech = material.stack_origin_tech.Copy()
+	if(islist(material.stack_origin_tech))
+		origin_tech = material.stack_origin_tech.Copy()
 	perunit = SHEET_MATERIAL_AMOUNT
 
 	if(apply_colour)