Origin

Wolverine's bones

Captain America's Shield

Adamantium is the strongest metal known to man in the Marvel Universe. Wolverine's Claws were coated in adamantium in a government laboratory experiment. Wolverine:char:1440]]'s adamantium coated bones are unbreakable. Although Captain America's shield has been described by some Silver Age writers as adamantium, in fact according to current Marvel canon its creation predates the invention of adamantium and appears to have inspired its creation.

Adamantium is a molecular iron compound discovered by Dr. Myron MacLain. In the 1940s as an American government scientist, MacLain was working with Vibranium. For months he attempted to fuse this alien ore with iron. Finally the task was accomplished unbeknowst to MacLain while he was asleep. He awoke to find -- somehow -- a mystery disk of nigh indestructible metal was eventually turned into Captain America's shield.

For decades, MacLain tried to replicate what happened in that laboratory that night. Eventually he was able to create a compound called True Adamantium which is nearly as strong as the materials found in Captain America's sheild. Wolverine's bones were laced with this True Adamantium. It is apparently also this form of Adamantium that was used by Lord Dark Wind, father of Lady Deathstrike, in his experiments to produce Japanese supersoldiers.

Objects made of Adamantium

Objects made of Adamantium in the Marvel Universe include: Captain America's shield, Battlestar's shield, Wolverine's skeleton and claws, Sabretooth's skeleton and claws, X-23's claws, a unique set of Doctor Octopus's robotic arms, Lady Deathstrike's skeleton and claws, Cyber's skin and claws, Moon Knight's crescent blades and some of his other accessories, Bullseye's spinal column, parts of Deathlok's body and skeleton, T.E.S.S.-One's robotic body, parts of Ultron's body and Hammerhead's skull, Mr. Fantastic's lab for extremely dangerous experimentation, a layer of the superhuman containment facility The Vault, a suit of armor once worn by Stilt-Man and Maverick's Knife, Omega Red's tentacles.

Types of adamantium

Omega Red's tentacles

• True adamantium

This type is the mother of all adamantiums; it is impossible to break. It could withstand a nuclear bomb, though Thor with all his strength and Mjolnir has slightly dented a small cylinder of it. Being this strong, it is very rare and expensive to create/manipulate and is top secret in the US government, though it has shared it with some of their "allies".

• Secondary adamantium

This type is much more easier to work with, making it much more cost effective though at the expense of its strength. Someone with super-strength (say the Hulk) can break it or warp it. Also referred to as Adamantium Steel.

• Adamantium beta

This was created by an experiment involving Wolverine. As a side effect of bonding true adamantium with his bones, and his rapid healing ability there was a molecular change which has adapted adamantium to the biology of normal bone. This Adamantium acts like a biological component, regenerating as his bones do.

• Carbonadium

Russia wanted to create its own type of adamantium, and thus carbonadium was born. This form of adamantium is not as durable as true adamantium, but it is also flexible. For most purposes, however, carbonadium is still virtually indestructable. Omega Red is probably the best known to use this metal with his tentacles, which act as a conduit for his energy draining powers. For more information see Carbonadium.

Breaking the Unbreakable

Though adamantium is said to be unbreakable and indestructible, there have been instances when objects made of the metal have been damaged. Images in Gallery.

Wolverine: The End

In Wolverine: The End, a tale that told about an elderly Wolverine in the future, some of Logan's claws were broken. How they got in this condition was never specified.

Ulimate Wolverine vs Hulk

Ultimate Spinal Surgery

In the still-unfinished miniseries Ultimate Wolverine Vs Hulk, it appears like Hulk breaks adamantium when he rips the mutant in half. Upon closer inspection and the application of a little logic, it's becomes apparent that though Hulk did rip Wolverine apart, he didn't actually break adamantium. For the clearest explanation as to why Wolverine's spine, but not the adamantium, could be broken, read the following.

Satyrquaze says:

"As far as Hulk breaking Wolverine in half... (quick biology and metallurgy lesson here) Despite propaganda saying otherwise, Wolverine's skeleton is not completely coated with adamantium, if it were he couldn't move. Adamantium porously coats each bone individually (and it would have to be porous because blood and oxygen is required to get inside the bone to the marrow for a person to live). Also there is a malleable disc between each bone (especially in vertebrae in the spine) which allows freedom of movement along with joints and ligaments(which wouldn't be coated in adamantium if Wolverine hopes to do things like walk, stand, move in the slightest...).Now what Hulk did was indeed rip Logan apart, but it's most likely that Wolverine's spine separated at it's weakest point (the discs between each vertebra) and everything tore apart quite easily from there. So no, Hulk more than likely didn't break adamanium at all in this instance. Not to say that he couldn't if suitably pissed."

Hulk can damage adamantium, or at least adamantium alloys (as seen below), but he did not do so in this instance.

Adamantium Ball

In MARVEL TEAM-UP #18, Hulk fought the villain Blastaar in a factory built with an adamantium alloy (not true admanatium). To defeat the enemy, he wrapped the metal around him, formed a ball, and threw him in the sea.

MODOK

In Incredible Hulk #167, the Hulk shatters MODOK's armor, which is an alloy of adamantium (but not true adamantium).

Anti-Metal

This rare substance also known as Antarctic vibranium can produce vibrations of a specific wavelength that can liquefy all metal including adamantium.

Dogs of War

In Incredible Hulk :Furture Imperfect #1, Maestro explains that he has created mechanical dogs (Dogs o' War) with jaws capable of crushing adamantinum in 7.3 seconds. That feat is never depicted on-panel. Hulk destroys the robot canine.

Captain America's Shield

Captain America's shield, which is an adamantium-vibranium alloy,  has been broken five times in the history of comics. The Molecule Man once destroyed the shield (along with Mjolnir, Namor's indestructible armor, and the Silver Surfer's board) by unmaking them on the molecular level. Klaw and Dr. Doom (both amped by the power of The Beyonder) damaged the shield on separate occasions. Thanos, wielding the Infinity Gauntlet, effortlessly shattered the shield with a backhand. Finally, King Thor destroyed the shield with eye beams in an alternate universe.

Molecule Man

Klaw

Dr. Doom

Thanos

King Thor