Is Coldsteel Heart legal in Standard, Modern, and Commander?

Coldsteel Heart is legal in: Modern, Legacy, Vintage, Commander, Historic.

What type of card is Coldsteel Heart?

Coldsteel Heart is a Snow Artifact. Its oracle text reads: "This artifact enters tapped. As this artifact enters, choose a color. {T}: Add one mana of the chosen color. *The Phyrexian death machine awoke, its coldsteel heart imbuing it with sinister new power.*"