Lorde treated her fans to quite the surprise Thursday evening (March 1), debuting a brand new song during her concert set in Milwaukee, Wisconsin.

Kicking off the North American leg of her Melodrama World Tour at the BMO Harris Bradley Center, Lorde premiered a hypnotic, tropical-tinged song, apparently called "Precious Metals," that was reportedly originally written for Melodrama before being cut from the album's final track list.

Watch a clip of the first-time performance below:

In addition to the previously unreleased track, the New Zealand pop star also performed an achy, moving cover of Frank Ocean's song, "Solo," off the rapper's album Blonde. Watch below:

Check out Lorde's full tour set list, below:

1. "Sober"
2. "Homemade Dynamite"
3. "Tennis Court"
4. "Magnets" (Disclosure cover)
5. "Buzzcut Season"
6. "400 Lux"
7. "Ribs"
8. "The Louvre"
9. "Hard Feelings"
10. "Yellow Flicker Beat"
11. "Writer in the Dark"
12. "Solo" (Frank Ocean cover)
13. "Liability"
14. "Sober II (Melodrama)"
15. "Supercut"
16. "Royals"
17. "Perfect Places"
18. "Green Light"
19. "Loveless"
20. "Precious Metals" (unreleased song)
21. "Team"

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