What are qraqeb, the Gnawa metal castanets?

If the guembri is the heartbeat of Gnawa music, the qraqeb are its hammering pulse. Each one is a pair of heavy iron plates, shaped a bit like a figure-eight or a dumbbell, joined by a leather cord that loops around the fingers. A player holds two in each hand and snaps them open and shut, so four metal plates are clashing in fast, rolling patterns. The sound is enormous — bright, ringing, almost industrial.

People often say qraqeb sound like a steam train picking up speed, and that is exactly right. The Gnawa themselves trace the rhythm to the rattle of the chains and shackles their enslaved ancestors wore, transformed into something powerful and celebratory. When a line of dancers each play a pair and move together, the wall of metallic sound is overwhelming in the best way, and it is what tips a ceremony from music into trance.

You feel qraqeb as much in your chest as in your ears. In Essaouira during the Gnaoua festival, troupes parade through the streets in white robes and embroidered caps, spinning the tasselled hats on their heads while the qraqeb roar — it is pure adrenaline. Even outside festival season, any Gnawa group you encounter in Marrakech’s Jemaa el-Fnaa or in a riad performance will have them, and the rhythm is irresistibly physical.

They are also the easiest Gnawa instrument to bring home: you can buy a pair in the Essaouira or Marrakech medina for a few dirhams, and players are usually delighted to show you the basic open-shut grip. Fair warning — they are loud, and harder to play in tight rolling patterns than they look. But there is no better souvenir of how a Moroccan rhythm gets into your body.