diff --git a/mods/nodes/init.lua b/mods/nodes/init.lua
index f7cb2a5..b458b1f 100644
--- a/mods/nodes/init.lua
+++ b/mods/nodes/init.lua
@@ -466,7 +466,7 @@ for n, v in pairs({"black", "violet", "brown", "cyan",
 		groups = {pickaxe = 1, node = 1},
 		sounds = sounds.stone,
 	})
-	make_stair_slab("hardened_clay_" .. v, nm(v .. " hardened clay"), {axe = 1, node = 1}, "_breakable", "", sounds.stone, tex)
+	make_stair_slab("hardened_clay_" .. v, nm(v .. " hardened clay"), {pickaxe = 1, node = 1}, "_breakable", "", sounds.stone, tex)
 	frame.register("nodes:hardened_clay_" .. v .. "_breakable")
 end