add silver-spool recipes only if silver is present

crafts.lua

@@ -16,6 +16,10 @@ local materials = {
 	silicon = "mesecons_materials:silicon",
 }
 
+if minetest.get_modpath("moreores") then
+	materials.silver_ingot = "moreores:silver_ingot"
+end
+
 if minetest.get_modpath("mcl_core") then
 	materials = {
 		dirt = "mcl_core:dirt",
@@ -376,6 +380,7 @@ minetest.register_craft( {
 	},
 })
 
+if materials.silver_ingot then
 	minetest.register_craft( {
 		output = "basic_materials:silver_wire 2",
 		type = "shapeless",
@@ -395,3 +400,4 @@ minetest.register_craft( {
 			materials.silver_ingot,
 		},
 	})
+end