diff --git a/README.md b/README.md
index 7ef1d5a..b177b99 100644
--- a/README.md
+++ b/README.md
@@ -93,7 +93,7 @@ You can find the old textures and sounds by going back to previous commits in Gi
 * [ ] Swiftwolf's Rending Gale (maybe rename?)
 * [ ] Mind, Life, Body and Soul Stones (Mind = MCL only)
 * [ ] Talisman of Repair (will only work in player inventory, not Alchemical Chests like ProjectE)
-* [ ] Gem of Eternal Density (will only work on right click, not automatically).
+* [x] Gem of Eternal Density (will only work on right click, not automatically).
 * [ ] Change energy collector recipes to match ProjectE
 * [ ] Update screenshots
 * [x] Update media licenses
@@ -125,6 +125,7 @@ You can find the old textures and sounds by going back to previous commits in Gi
     * Added achivements/advancements awards (mostly matching ProjectE, but with some missing or added).
     * Replaced Exchange Orbs with Klein Stars and Magnum Stars
     * Added storage blocks for Alchemical Coal, Mobius Fuel, and Aeternalis Fuel
+    * Added Gem of Eternal Density
 * Changes:
     * Most textures and all sounds are now from ProjectE/EE2. See license section for details.
     * Several improvements to tools:
diff --git a/exchangeclone/armor.lua b/exchangeclone/armor.lua
index b355d6e..c2a35d6 100644
--- a/exchangeclone/armor.lua
+++ b/exchangeclone/armor.lua
@@ -285,13 +285,14 @@ else
     })
     minetest.register_on_player_hpchange(function(player, hp_change, reason)
         if hp_change < 0 then
+            local damage = -hp_change
             local _, armor_inv = armor:get_valid_player(player, "3d_armor")
             local blocked = 0
             for i = 1, 6 do
                 local itemstack = armor_inv:get_stack("armor", i)
-                blocked = blocked + get_blocked_damage(itemstack, hp_change, reason)
+                blocked = blocked + get_blocked_damage(itemstack, damage, reason)
             end
-            return math.max(0, hp_change - blocked)
+            return -math.max(0, damage - blocked)
         else
             return hp_change
         end
@@ -364,7 +365,7 @@ minetest.register_craft({
 if exchangeclone.mtg then
     minetest.register_tool("exchangeclone:shield_dark_matter", {
         description = "Dark Matter Shield (deprecated)\nYou still have this so you can turn it into EMC.\nAnd no, it's not supposed to have a texture.",
-        groups = {disable_repair = 1, not_in_creative_inventory = 1}
+        groups = {disable_repair = 1, not_in_creative_inventory = 1, not_in_craft_guide = 1}
     })
     exchangeclone.register_craft({
         output = "exchangeclone:shield_dark_matter",
@@ -382,7 +383,7 @@ if exchangeclone.mtg then
 
     minetest.register_tool("exchangeclone:shield_red_matter", {
         description = "Red Matter Shield (deprecated)\nYou still have this so you can turn it into EMC.\nAnd no, it's not supposed to have a texture.",
-        groups = {disable_repair = 1, not_in_creative_inventory = 1}
+        groups = {disable_repair = 1, not_in_creative_inventory = 1, not_in_craft_guide = 1}
     })
     exchangeclone.register_craft({
         output = "exchangeclone:shield_red_matter",
diff --git a/exchangeclone/gem_of_eternal_density.lua b/exchangeclone/gem_of_eternal_density.lua
new file mode 100644
index 0000000..b8f6289
--- /dev/null
+++ b/exchangeclone/gem_of_eternal_density.lua
@@ -0,0 +1,107 @@
+exchangeclone.density_targets = {
+    exchangeclone.itemstrings.iron,
+    exchangeclone.itemstrings.gold,
+    exchangeclone.itemstrings.diamond,
+    "exchangeclone:dark_matter",
+    "exchangeclone:red_matter",
+}
+
+local function get_gem_description(itemstack)
+    local meta = itemstack:get_meta()
+    local current_target = math.max(meta:get_int("density_target"), 1)
+    local target_message = "Target: "..ItemStack(exchangeclone.density_targets[current_target]):get_short_description()
+    local emc = exchangeclone.get_item_emc(itemstack:get_name())
+    local stored = exchangeclone.get_item_emc(itemstack) - emc
+    return "Gem of Eternal Density\n"..target_message.."\nEMC value: "..exchangeclone.format_number(emc).."\nStored EMC: "..exchangeclone.format_number(stored)
+end
+
+local function gem_action(itemstack, player, pointed_thing)
+    local click_test = exchangeclone.check_on_rightclick(itemstack, player, pointed_thing)
+    if click_test ~= false then
+        return click_test
+    end
+
+    local meta = itemstack:get_meta()
+    if player:get_player_control().aux1 then
+        local current_target = math.max(meta:get_int("density_target"), 1)
+        if player:get_player_control().sneak then
+            current_target = math.max(1, current_target - 1)
+        else
+            current_target = math.min(#exchangeclone.density_targets, current_target + 1)
+        end
+        minetest.chat_send_player(player:get_player_name(), "Target: "..ItemStack(exchangeclone.density_targets[current_target]):get_short_description())
+        meta:set_int("density_target", current_target)
+        meta:set_string("description", get_gem_description(itemstack))
+        return itemstack
+    end
+
+    local inv = player:get_inventory()
+    local list = inv:get_list("main")
+    -- Don't include hotbar
+    local min = exchangeclone.mcl and 10 or 9
+    if player:get_wield_index() >= min then return end
+
+    local total_emc = exchangeclone.get_item_emc(itemstack) - exchangeclone.get_item_emc(itemstack:get_name())
+
+    local target = exchangeclone.density_targets[math.max(meta:get_int("density_target"),  1)]
+
+    for i = min, #list do
+        local stack = list[i]
+        if stack:get_name() ~= target then
+            local emc = exchangeclone.get_item_emc(stack) or 0
+            if emc > 0 then
+                total_emc = total_emc + emc
+                list[i] = ItemStack("")
+            end
+        end
+    end
+
+    inv:set_list("main", list)
+
+    if not (total_emc and total_emc > 0) then return end
+
+    local target_emc = exchangeclone.get_item_emc(target)
+    local stack_max = ItemStack(target):get_stack_max()
+    local num_to_add, remainder_emc = math.floor(total_emc/target_emc), total_emc % target_emc
+    local num_stacks, remainder = math.floor(num_to_add/stack_max), num_to_add%stack_max
+
+    if num_stacks > 0 then
+        for i = 1, num_stacks do
+            num_stacks = num_stacks - 1
+            local extra = inv:add_item("main", ItemStack(target.." "..stack_max))
+            if extra:get_count() > 0 then
+                remainder = remainder + extra:get_count()
+                break
+            end
+        end
+    end
+
+    if num_stacks > 0 then
+        remainder = remainder + num_stacks*stack_max
+    else
+        remainder = inv:add_item("main", ItemStack(target.." "..remainder)):get_count()
+    end
+    if remainder > 0 then
+        remainder_emc = remainder_emc + remainder*target_emc
+    end
+    exchangeclone.play_sound(player, "exchangeclone_enable")
+    meta:set_int("exchangeclone_emc_value", exchangeclone.get_item_emc(itemstack:get_name()) + remainder_emc)
+    meta:set_string("description", get_gem_description(itemstack))
+    return itemstack
+end
+
+minetest.register_tool("exchangeclone:gem_of_eternal_density", {
+    description = "Gem of Eternal Density",
+    inventory_image = "exchangeclone_gem_of_eternal_density.png",
+    on_secondary_use = gem_action,
+    on_place = gem_action
+})
+
+minetest.register_craft({
+    output = "exchangeclone:gem_of_eternal_density",
+    recipe = {
+        {exchangeclone.itemstrings.diamond, exchangeclone.itemstrings.obsidian, exchangeclone.itemstrings.diamond},
+        {"exchangeclone:dark_matter", exchangeclone.itemstrings.diamond, "exchangeclone:dark_matter"},
+        {exchangeclone.itemstrings.diamond, exchangeclone.itemstrings.obsidian, exchangeclone.itemstrings.diamond}
+    }
+})
\ No newline at end of file
diff --git a/exchangeclone/init.lua b/exchangeclone/init.lua
index 93661a8..e6e1c1a 100644
--- a/exchangeclone/init.lua
+++ b/exchangeclone/init.lua
@@ -136,6 +136,7 @@ dofile(modpath.."/infinite_food.lua")
 dofile(modpath.."/alchemical_chests.lua")
 dofile(modpath.."/transmutation_table.lua")
 dofile(modpath.."/furnaces.lua")
+dofile(modpath.."/gem_of_eternal_density.lua")
 if minetest.get_modpath("awards") then
 	dofile(modpath.."/awards.lua")
 end
diff --git a/exchangeclone/multidig.lua b/exchangeclone/multidig.lua
deleted file mode 100644
index e69de29..0000000
diff --git a/exchangeclone/shovels.lua b/exchangeclone/shovels.lua
index a1ae761..30751dd 100644
--- a/exchangeclone/shovels.lua
+++ b/exchangeclone/shovels.lua
@@ -152,7 +152,7 @@ minetest.register_tool("exchangeclone:red_matter_shovel", {
 		damage_groups = {fleshy=7},
 		punch_attack_uses = 0,
 		groupcaps={
-			crumbly = {times=exchangeclone.get_mtg_times(16, nil, "crumbly") maxlevel=5},
+			crumbly = {times=exchangeclone.get_mtg_times(16, nil, "crumbly"), maxlevel=5},
 		},
 	},
 	on_place = shovel_on_place,
diff --git a/exchangeclone/textures/exchangeclone_gem_of_eternal_density.png b/exchangeclone/textures/exchangeclone_gem_of_eternal_density.png
new file mode 100644
index 0000000..03d1eec
Binary files /dev/null and b/exchangeclone/textures/exchangeclone_gem_of_eternal_density.png differ
diff --git a/exchangeclone/tool_upgrades.lua b/exchangeclone/tool_upgrades.lua
index 2d346e5..1b32a7f 100644
--- a/exchangeclone/tool_upgrades.lua
+++ b/exchangeclone/tool_upgrades.lua
@@ -83,7 +83,7 @@ local function upgrader_action(pos)
 
     local new_emc = exchangeclone.get_item_emc(new_tool) + exchangeclone.get_item_emc(upgrade:get_name())
 
-    new_tool:get_meta():set_string("exchangeclone_emc_value", tostring(new_emc))
+    new_tool:get_meta():set_int("exchangeclone_emc_value", new_emc)
 
     inv:set_stack("dst", 1, new_tool)
 
diff --git a/gem_of_eternal_density.lua b/gem_of_eternal_density.lua
deleted file mode 100644
index b7bf10c..0000000
--- a/gem_of_eternal_density.lua
+++ /dev/null
@@ -1,60 +0,0 @@
-exchangeclone.density_targets = {
-    exchangeclone.itemstrings.iron,
-    exchangeclone.itemstrings.gold,
-    exchangeclone.itemstrings.diamond,
-    "exchangeclone:dark_matter",
-    "exchangeclone:red_matter",
-}
-
-local function gem_action(itemstack, player, pointed_thing)
-    local click_test = exchangeclone.check_on_rightclick(itemstack, player, pointed_thing)
-    if click_test ~= false then
-        return click_test
-    end
-
-    local meta = itemstack:get_meta()
-    if player:get_player_controls().aux1 then
-        local current_target = meta:get_int("density_target") or 1
-        if player:get_player_controls().sneak then
-            current_target = math.max(1, current_target - 1)
-        else
-            current_target = math.min(#exchangeclone.density_targets, current_target + 1)
-        end
-        minetest.chat_send_player(player:get_name(), "Target: "..ItemStack(exchangeclone.density_targets[current_target]):get_short_description())
-        meta:set_int("density_target", current_target)
-        return itemstack
-    end
-
-    local inv = player:get_inventory()
-    local list = inv:get_list("main")
-    -- Don't include hotbar
-    local min = exchangeclone.mcl and 10 or 9
-    if player:get_wield_index() >= min then return end
-
-    local total_emc = meta:get_int("density_stored") or 0
-    for i = min, #list do
-        local stack = list[i]
-        local emc = exchangeclone.get_item_emc(stack) or 0
-        if emc > 0 then
-            total_emc = total_emc + emc
-            list[i] = ItemStack("")
-        end
-    end
-
-    if not (total_emc and emc > 0) then return end
-
-    local target = exchangeclone.density_targets[meta:get_int("density_target") or 1]
-    local target_emc = exchangeclone.get_item_emc(target)
-
-    local stack_max = ItemStack(target):get_stack_max()
-    local num_to_add = math.floor(total_emc/target_emc)
-    local num_stacks, remainder = math.floor(num_to_add/stack_max), num_to_add%stack_max
-
-    for i = 0, num_stacks do
-        local extra = inv:add_item("main", ItemStack(target.." "..stack_max))
-        if extra:get_count() > 0 then
-            break
-        else
-    end
-
-end
\ No newline at end of file
diff --git a/zzzz_exchangeclone_init/lib.lua b/zzzz_exchangeclone_init/lib.lua
index 1cfb556..9e9e661 100644
--- a/zzzz_exchangeclone_init/lib.lua
+++ b/zzzz_exchangeclone_init/lib.lua
@@ -69,7 +69,6 @@ function exchangeclone.get_item_emc(item)
     end
 
     if type(item) == "userdata" then
-        minetest.log("thingithingi")
         local meta_emc_value = tonumber(item:get_meta():get_string("exchangeclone_emc_value"))
         if meta_emc_value then minetest.log(dump(meta_emc_value)) return math.max(0, meta_emc_value) end
     end
@@ -354,6 +353,7 @@ end
 exchangeclone.itemstrings = {
     cobble =            exchangeclone.mcl and "mcl_core:cobble"             or "default:cobble",
     redstoneworth =     exchangeclone.mcl and "mesecons:redstone"           or "default:obsidian",
+    obsidian =          exchangeclone.mcl and "mcl_core:obsidian"           or "default:obsidian",
     glowstoneworth =    exchangeclone.mcl and "mcl_nether:glowstone_dust"   or "default:tin_ingot",
     coal =              exchangeclone.mcl and "mcl_core:coal_lump"          or "default:coal_lump",
     iron =              exchangeclone.mcl and "mcl_core:iron_ingot"         or "default:steel_ingot",
@@ -1100,13 +1100,6 @@ function exchangeclone.add_range_setting(name, data)
     exchangeclone.tool_levels.range[name] = data
 end
 
-local function calculate_time_from_time(time, speed, efficiency)
-    if not efficiency then return time end
-    local hardness = (2/3)*time*speed
-    speed = speed + efficiency*efficiency + 1
-    return math.ceil(30/(speed/hardness))/20
-end
-
 -- A table of estimated hardness values for MTG
 -- Calculated by finding MTG nodes with the right group, then looking up the Minecraft hardness for them
 local hacky_workaround = {
@@ -1140,7 +1133,9 @@ function exchangeclone.get_groupcaps(item, efficiency)
 
         if not groupcaps then return end
         for group, def in pairs(groupcaps) do
-            groupcaps[group].times = exchangeclone.get_mtg_times(speed, efficiency, group)
+            local test_group = group
+            if test_group == "exchangeclone_dirt" then test_group = "crumbly" end
+            groupcaps[group].times = exchangeclone.get_mtg_times(speed, efficiency, test_group)
         end
         return groupcaps
     end