diff --git a/scripts/portalgun.lua b/scripts/portalgun.lua
index bd37666..e490511 100644
--- a/scripts/portalgun.lua
+++ b/scripts/portalgun.lua
@@ -486,7 +486,7 @@ function portalgun_onuse(itemstack, user, pointed_thing, mode) -- using the gun
             --     minetest.sound_play("portalgun_error", {pos = pos, max_hear_distance = 5, gain = 3})
             --     return itemstack
             -- end
-            local istestblock = string.find(nname, "portalgun:testblock", 1)
+            local istestblock = string.find(nname, "portalgun:testblock", 1) or string.find(nname, "mesecons_lightstone:lightstone_white", 1)
             if not istestblock then
                 minetest.sound_play("portalgun_error", {pos = pos, max_hear_distance = 5, gain = 3})
                 return itemstack