Orikalkum is an ore that cannot currently be mined or smithed by players. Forcae describes Orikalkum in his journal as a strong, red metal from which dragon equipment was made.  The only known users of the metal are the Dragonkin, who brought the ore with them from their homeworld in the Old Revision. The equipment made from Orikalkum is named "Dragon" after them.
According to the Dactyl Dragonkin Forcae, Orikalkum ore originates from the Dragonkin's homeworld in the previous revision of the universe. The Dragonkin seem to have brought limited quantities of the Dragon equipment made from the ore and perhaps even the ore itself to Gielinor with them after they were enslaved by Jas.
At some point, it is likely to have been smithed and smelted at the Dragon Forge in the Ancient Cavern, as it was created by the Dragonkin and is the only known place hot enough to melt down and smith the metal. While attempts have been made to melt it down through other methods, so far, none have been successful. A faction of Dragonkin known as the Necrosyrtes are believed to have either created or at least possess a large number of dragon armour and weapons.
Fairy Aeryka suggests that the Dragonkin gave the dragon equipment they smithed to people they liked, explaining why it can be found all over Gielinor. Jukat, the fairy in Zanaris selling dragon longswords and daggers, advertises that they come "straight from Frenaskrae[sic]". This would suggest that the Dragonkin may have left some dragon equipment on Freneskae. Additionally, the Tormented demons have had their flesh fused with pieces of Dragon armour by Lucien, and as such the ruined pieces of their body they drop can be smithed at the Dragon Forge to create the Dragon platebody.
Initially, Orikalkum was to be renamed Drakolith, as the Greek inspiration behind the name was more appropriate for icyenes rather than dragonkin. However, after player feedback, the original name was kept, with the metal being created from Oricalcite ore and Drakolith ore. 
- Orikalkum is based on the mythical metal Orichalcum, a metal associated with Atlantis and found in Plato's writings, and is also used to describe the alloy in some Roman coins. It is currently believed to be a form of brass created by the Greeks.
- ^ Forcae, "Forcae's journal", RuneScape. "Orikalkum. Think about it. Our metal, strong, durable, pliable. Our metal infused with their strength. A great Orikalkum dragon."
- ^ Forcae, "Forcae's journal", RuneScape. "I will need a pure vein, but for that I will have to find a way back to our world. This curious gate seems like it could be capable of taking me there, to our world empty of [illegible]."
- ^ Mod Jack. TL;DW 358 - Mining and Smithing Rework Showcase. Reddit. 12 December 2017. "The reason the lore book talks about orichalcum is that that's the name I gave it in the original M&S rework design from about five years ago. Since then we've developed the races and their cultures more fully, and Icyene have a strong greek influence and Dragonkin don't."
- ^ Mod Jack. Design - Both - Metals.*