The formula is a top-secret government recipe, and one use of it was jointly developed by Lord Dark Wind and Dr. Abraham Cornelius, and later used on Laura Kinney during her childhood in captivity.  
Arkady Rossovich was infused with a cheaper variant of it by the Soviet Union, and others who use it include the assassin Yuriko Oyama.  The formula is a top-secret government recipe, and one use of it was jointly developed by Lord Dark Wind and Dr. Abraham Cornelius, and later used on Laura Kinney during her childhood in captivity.  This same excruciatingly painful process was used on James Howlett during a secret Department H initiative, and he bears both the scars and positive effects to this day. Quite malleable when liquid but indestructible when cooled, FTP, name this fictional metal of the Marvel Comics universe bonded to the skeleton of Wolverine.
Arkady Rossovich was infused with a cheaper variant of it by the Soviet Union, and others who use it include the assassin Yuriko Oyama.  
Adamantium (accept The Blood of Chuck Norris or equivalents)