Guide:Renewability

In Terraria, an item or block is considered "renewable" if it can be created indefinitely within a single world.

There are many forms of renewable resources:
 * Items obtained by killing various enemies or buying them from NPCs are renewable, as most of the former and all of the latter can be respawned infinitely. All enemies and NPC drops are technically infinite. This also means that money is renewable. For tips on making money in large quantities, see Guide:Making money.
 * Fishing for the items, either as direct catches or via Crates or Angler rewards.
 * Any item which is crafted solely from renewable items is itself renewable, even if it requires a non-renewable crafting station.
 * Use of game mechanics:
 * Some items need to be harvested, by planting the appropriate seeds.
 * Others can spontaneously spawn in predictable environments.
 * Liquids behavior allows a number of ways to combine liquids, increasing their volume over time, and also to create certain blocks by combining them.
 * Miscellaneous methods such as using the Sandgun with ammo-reduction effects.

Non-renewable items are:
 * Any item which has a non-renewable item in its crafting recipe.
 * Some items are found in specific Chests, of which a limited number spawn with a world, and a few of those cannot also be obtained by fishing. Most of the chests themselves are also non-renewable.
 * A few items are created with the world in particular locations, and cannot otherwise be created in world. This includes furnitures and materials from several fixed structures, notably the Dungeon, the Jungle Temple, the Underworld's Ruined Houses, and Altars. These structures also tend to include location-specific chests.
 * Some blocks are created with the world, and may be quite plentiful, but cannot actually be craftyed. This applies to all Soils types except for Sand, Granite and Snow (via the Frost Legion). It also applies to Hive blocks, and therefore to the Queen Bee's drops.
 * Some types of natural Wall cannot be harvested or crafted by the player. In some cases, this is important for game mechanics to work.

Here is a list of renewable resources separated by categories.

Wood
Wood is arguably the most common renewable resource. Chopping down Trees will yield the biome-specific Wood that the tree was growing on. Most trees also drop Acorns that can be planted to grow new ones. Jungle trees don't drop acorns, but can spontaneously grow on Jungle Grass.

All types of wood can be used for structures, background walls, furniture, and platforms.

Sand
Sand, and by extension, Glass, is an infinite resource if you have the right equipment:
 * Antlions can shoot projectiles that creates more Sand, albeit very slowly.
 * A Sandgun used with ammunition-conserving methods such as Ammo Reservation Potion, Necro Armor set, and/or Ammo Box, can place more sand than it uses, thus "farming" sand.

By extension, Ebonsand, Crimsand and Pearlsand are also renewable, since the normal variant can be intentionally transformed prior to harvesting. Be aware that the blocks can only be converted in Hardmode.

Miscellaneous Blocks

 * Granite Blocks are renewable, as they drop from Granite Golems and Elementals.
 * Sturdy Fossils are dropped by Basilisks in Hardmode.
 * Cobwebs automatically regenerate on naturally occurring Spider Walls found in Spider Nests. However, beware that these walls are themselves non-renewable: they are only created during world generation, and can't be picked up after removal.
 * Snow is renewable, as it can be created and dropped by the enemies of the Frost Legion invasion. The required summoning item for the Frost Legion appears only during the Christmas season.

Gel
Gel is an enemy drop dropped by every types of Slimes. It is used for many recipes, beginning with the Torch. With a Solidifier, it can be converted to Slime Blocks.

Unlike other slimes, Pinky drops Pink Gel. It is still renewable, but is extremely hard to get in large amounts.

Bomb
Bombs are an infinite resource since they can be bought from the Demolitionist, and created infinitely by wiring a Bomb Statue.

Bomb Fish are equivalent to Sticky Bombs, and are obtained from fishing, making these also renewable.

Crops and Herbs

 * Cactus is an infinite resource as long as there is sand around, as it grows naturally.
 * Hay is produced by cutting tall grass with a Sickle.
 * Pumpkins can be grown from Pumpkin Seeds, which the Dryad always sells. They also spawn naturally during Halloween.
 * Coral is renewable as it grows on the Ocean bottom.
 * Regular, Glowing, and Vile or Vicious Mushrooms will grow on their respective grass types.
 * All herbs will spawn indefinitely in their respective Biome or, and can be manually planted with their respective Seeds.

Ores
With the exception of Hellstone and Chlorophyte, all Ores are renewable through various means:

Standard Pre-Hardmode ores
Copper or Tin, Iron or Lead, Silver or Tungsten, and Gold or Platinum can be found in the ground throughout the game, and can also be obtained in smaller quantities by use of the Extractinator. Neither of those processes are renewable, but the ores are renewable, through two methods: They can be obtained by opening Wooden Crates, or from Slimes as bonus drops.

Crimtane and Demonite Ore
Demonite and Crimtane Ores can be dropped by their respective evil biome boss (Eater of Worlds for Demonite, Brain of Cthulhu for Crimtane). However, only one Evil ore can be dropped by Eye of Cthulhu per world. If the other evil biome is transported into a world, it will then be renewable.

Meteorite
Meteorite is a major renewable resource in pre-Hardmode. The first meteorite crash occur on a 50% chance after smashing a Shadow Orb or Crimson Heart. They spawn Meteor Heads, which can drop Meteorite ore, but only in pre-Hardmode.

Standard Hardmode Ores
Cobalt or Palladium, Mythril or Orichalcum, and Adamantite or Titanium are all renewable, as these can be found in Crates during Hardmode.

Enemy and NPC drops
Any item which can be gained by killing something is renewable (with the exception of non-renewable drops from Queen Bee, like the Bee Keeper). Killing enemies and bosses is straightforward (if sometimes non-trivial). NPCs can also be killed, with more effort. Visit the NPC, NPC Drops, and Drops pages for a list of all of them. This includes money, which can also be gained by selling other renewable items.

An unorthodox case of this is the fact that Demonite Brick is renewable in Corruption worlds despite the ebonstone in the recipe being non-renewable, as small quantities are obtained upon killing the Wall of Flesh. A similar principle applies to Crimtane Brick in a Crimson world.

Purchased Items
Since money is renewable, all items purchased from NPC's are renewable. Most NPC's have items to sell, the exceptions being the Guide, Nurse, Angler, Tax Collector, and Old Man. The Angler and the Dye Trader can furthermore provide items as quest rewards. Visit the NPCs' respective pages to view the items they sell.

Fishing
Items obtained by Fishing are all renewable. Visit that page to view all Items obtainable from fishing. Many ores and bars (see above) can be obtained by way of Crates, as can many weapons, tools, and accessories, and even a crafting station. Additional items can be gotten from the Angler as quest rewards.

Dyes
All the "basic" dyes are either plants that spawn spontaneously, purchased, or mob drops. Quest-exclusive Dyes can be obtained from the Dye Trader as long as Strange Plants can grow to trade them in. All other dyes can be crafted from basic, purchased, and/or quest dyes.

Crystal Shards
Crystal Shards are renewable as they naturally grow on Pearlstone Blocks and Pink Ice Blocks in the Cavern.

On the, Crystal Shards are also dropped by Arch Demons, allowing for large-scale collection.

Fallen Stars
Fallen Stars will regularly fall from the sky every night, and are therefore renewable.

Critters
All the Critter types spawn spontaneously in their respective biomes.

Liquids
All liquids can be reproduced infinitely. By extension, all liquid-created Blocks (Obsidian, Honey Block, and Crispy Honey Block) can be created indefinitely.

Non-renewable Items
Non-renewable items are few enough that they can be listed individually. A few of those are "semi-renewable", produced by something that is plentiful but ultimately finite.

Plentiful but Finite

 * The various Soil types are created with the world, but only Sand and Granite, and (sometimes) Snow, can actually be created in world. Ignoring variations of grass, moss, and biome conversion, that leaves Dirt, Stone, Clay, Mud, Silt, Slush, Desert Fossil, Hardened Sand, Sandstone, Ice, Thin Ice, Ash, and Marble as plentiful but non-renewable. This extends to items created from these materials, including all craftable Statues, and several furniture sets: Frozen, Marble, Flesh, and (due to the stone needed for their bricks) Skyware, Meteorite, and Crystal.
 * Gems are found placed in the world, but the only other source for them is using an Extractinator on Silt, Slush, and Desert Fossils. Therefore gems (including Amber), are non-renewable, as is the Amber Mosquito item. Sturdy Fossils, however, are dropped by Basilisks in Hardmode, so those are renewable.
 * Hive blocks are found only in hives in the Jungle. Since Hive (or a Larva, which is only generated with the world) is needed to summon the Queen Bee, this makes the Queen Bee's drops (except Bottled Honey), and any item made with Bee Wax, plentiful but non-renewable (but still plentiful).
 * Chlorophyte ore is created by replacing mud, which can be crafted from dirt but is still non-renewable. In practice this makes chlorophyte "nearly unlimited", but it would be possible to deplete a world's mud/dirt; say, by using chlorophyte for large-scale building, or farming it for sale. All of this applies equally well to Shroomite and Spectre Bars, which are made from chlorophyte.
 * Some types of natural Wall cannot be harvested or crafted by the player; even harvestable walls will no longer be considered "natural" if they are harvested and replaced.
 * Natural walls do not suppress enemy spawning, while any placed walls can.
 * The Dungeon, Spider Nest, and Underground Desert (mini-)biome s are defined by the presence of their respective naturally generated walls.

Location Specific Generation
A few items are created with the world in particular locations, and cannot otherwise be created in world. This includes (but is not limited to) furnishings and materials from several fixed structures, notably the Dungeon, the Jungle Temple, the Underworld's Ruined Houses.
 * Varied Locations:
 * Many particular Paintings (see page for details)
 * Several decorative Banners (see page for details)
 * Assorted Chests (see page and/or list below)
 * The Enchanted Sword or Arkhalis.
 * Underground and Caverns:
 * Geyser Traps
 * Dart Traps
 * Non-craftable Statues
 * Sharpening Station
 * Jungle Temple:
 * Lihzahrd Bricks, and all matching furniture and statues
 * Lihzahrd Pressure Plates and traps: Spiky Ball Trap, Flame Trap, Spear Trap, Super Dart Trap, Wooden Spike
 * Lihzahrd Chest
 * Lihzahrd Furnace
 * Lihzahrd Altar
 * Dungeon:
 * Dungeon Bricks and most associated Furniture.
 * Alchemy Table
 * Water Bolt
 * Bone Welder (placed or in chests)
 * Valor (yo-yo) (in chests)
 * Catacomb
 * Underworld:
 * Most Obsidian Furniture
 * Hellforge
 * Hellstone ore
 * see also "Shadow Chests" below.

Location-Specific Chests
Various special chests spawn with a world, and even those chests which have corresponding Crates have a few items which are not found in their crates. In all cases, items are listed under only the first chest they appear in. All of the chests listed below are themselves uncraftable and non-renewable items.
 * Gold Chest: Most items are shared with other "generic" chests.
 * Spear
 * Wooden Boomerang
 * Blowpipe
 * Umbrella
 * Wand of Sparking
 * Herb Bag (the herbs and seeds it contains are renewable)
 * Band of Regeneration
 * Magic Mirror
 * Cloud in a Bottle
 * Hermes Boots (but renewable Sailfish boots are identical)
 * Shoe Spikes
 * Flare Gun
 * Lava Charm
 * Gold Chests in Pyramid:
 * Sandstorm in a Bottle
 * Pharaoh's Mask and Robe
 * Flying Carpet
 * Ice Chest
 * Ice Boomerang
 * Ice Blade
 * Ice Skates
 * Snowball Cannon
 * Blizzard in a Bottle
 * Flurry Boots (but renewable Sailfish boots are identical)
 * Ice Machine
 * Ice Mirror (identical to Magic Mirror)
 * Fish (item)
 * Ivy Chest
 * Seaweed
 * Flower Boots
 * Living Mahogany Wand
 * Rich Mahogany Leaf Wand
 * Honey Dispenser
 * Living Wood Chest
 * Living Wood Wand
 * Leaf Wand
 * Living Loom
 * Skyware Chest
 * Sky Mill
 * Water Chest
 * Trident
 * Breathing Reed
 * Flipper
 * Water Walking Boots
 * Beach Ball ( purchasable on Desktop)
 * Web Covered Chest
 * Web Slinger
 * Shadow Chest
 * Dark Lance
 * Flamelash
 * Flower of Fire
 * Sunfury
 * Hellwing Bow
 * the four-out-of-five Biome Chests in the Dungeon: Frozen, Jungle, Hallowed, and either Corruption or Crimson.
 * Their special prizes are likewise non-renewable: Staff of the Frost Hydra, Piranha Gun, Rainbow Gun, Scourge of the Corruptor, and Vampire Knives.

Non-renewable Crafting Stations
It seems worthwhile to summarize those crafting stations which are non-renewable (as listed above). Special mention for the Sharpening Station, which is not a crafting station but in some ways resembles one.
 * Alchemy Table
 * Bone Welder
 * Hellforge (And thus, the Hardmode Forges)
 * Honey Dispenser
 * Ice Machine
 * Lihzahrd Furnace
 * Living Loom
 * Sky Mill

zh:指南:可再生资源