diff --git a/README.md b/README.md
index e523a68..4fe8060 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # Gravel Sieve Mod
-This mod include two new tools:
- - a hammer to produce gravel from cobble
- - a sieve to sift gravel in order to find ores.
+This mod includes two new tools:
+ - a hammer to produce gravel from Cobblestone
+ - a sieve to sift gravel to find ores
 
 Browse on: ![GitHub](https://github.com/joe7575/Minetest-Gravelsieve)
 
diff --git a/description.txt b/description.txt
index e20287d..530c902 100644
--- a/description.txt
+++ b/description.txt
@@ -1 +1 @@
-This mod includes a hammer to produce gravel, and a sieve to sift gravel in order to find ores.
+This mod includes a hammer to produce gravel from Cobblestone and a sieve to sift gravel to find ores.
\ No newline at end of file
diff --git a/hammer.lua b/hammer.lua
index f52bb65..f438419 100644
--- a/hammer.lua
+++ b/hammer.lua
@@ -13,9 +13,6 @@
 	LGPLv2.1+
 	See LICENSE.txt for more information
 
-	History:
-	2017-06-04  v0.01  first version
-
 ]]--
 
 
@@ -23,7 +20,6 @@ gravelsieve.disallow = function(pos, node, user, mode, new_param2)
 	return false
 end
 
--- Handles rotation
 gravelsieve.handler = function(itemstack, user, pointed_thing)
 	if pointed_thing.type ~= "node" then
 		return
@@ -50,21 +46,15 @@ gravelsieve.handler = function(itemstack, user, pointed_thing)
 	return itemstack
 end
 
--- hammer
 minetest.register_tool("gravelsieve:hammer", {
 	description = "Hammer converts any kind of stone to gravel",
 	inventory_image = "gravelsieve_hammer.png",
 	on_use = function(itemstack, user, pointed_thing)
-		hammer.handler(itemstack, user, pointed_thing)
+		gravelsieve.handler(itemstack, user, pointed_thing)
 		return itemstack
 	end,
--- 	on_place = function(itemstack, user, pointed_thing)
--- 		hammer.handler(itemstack, user, pointed_thing)
--- 		return itemstack
--- 	end,
 })
 
-
 minetest.register_craft({
 	output = "gravelsieve:hammer",
 	recipe = {
diff --git a/init.lua b/init.lua
index 7b6af2d..a9988f2 100644
--- a/init.lua
+++ b/init.lua
@@ -14,7 +14,7 @@
 	See LICENSE.txt for more information
 
 	History:
-	2017-06-04  v0.01  first version
+	2017-06-14  v0.01  first version
 
 ]]--
 
@@ -25,6 +25,7 @@ gravelsieve = {
 dofile(minetest.get_modpath("gravelsieve") .. "/hammer.lua")
 
 
+-- Ore probability table  (1/n)
 local sieve_table = {
     iron_lump = 15,
     copper_lump = 15,
@@ -46,7 +47,6 @@ local function can_dig(pos, player)
 	local meta = minetest.get_meta(pos);
 	local inv = meta:get_inventory()
 	return inv:is_empty("dst") and inv:is_empty("src")
-    --return true
 end
 
 local function allow_metadata_inventory_put(pos, listname, index, stack, player)
@@ -79,7 +79,7 @@ end
 local function swap_node(pos, meta)
 	local node = minetest.get_node(pos)
 
-    idx = meta:get_int("idx")
+    local idx = meta:get_int("idx")
     idx = (idx + 1) % 4
     meta:set_int("idx", idx)
     node.name = "gravelsieve:sieve"..idx
@@ -217,7 +217,7 @@ end
 minetest.register_node("gravelsieve:gravel1", {
 	description = "Gravel sifted 1",
 	tiles = {"default_gravel.png"},
-	groups = {crumbly = 2, falling_node = 1},
+	groups = {crumbly = 2, falling_node = 1, not_in_creative_inventory=1},
 	sounds = default.node_sound_gravel_defaults(),
 	drop = {
 		max_items = 1,
@@ -231,7 +231,7 @@ minetest.register_node("gravelsieve:gravel1", {
 minetest.register_node("gravelsieve:gravel2", {
 	description = "Gravel sifted 2",
 	tiles = {"default_gravel.png"},
-	groups = {crumbly = 2, falling_node = 1},
+	groups = {crumbly = 2, falling_node = 1, not_in_creative_inventory=1},
 	sounds = default.node_sound_gravel_defaults(),
 	drop = {
 		max_items = 1,
@@ -245,7 +245,7 @@ minetest.register_node("gravelsieve:gravel2", {
 minetest.register_node("gravelsieve:gravel3", {
 	description = "Gravel sifted 3",
 	tiles = {"default_gravel.png"},
-	groups = {crumbly = 2, falling_node = 1},
+	groups = {crumbly = 2, falling_node = 1, not_in_creative_inventory=1},
 	sounds = default.node_sound_gravel_defaults(),
 	drop = {
 		max_items = 1,