CERN’ s Large Hadron Collider has detected the signals of two new four-quark states that are unusual because of their charges and their quark compositions. In the protons and neutrons that make up everyday matter, all the hadrons are of the three-quark variety. But quarks can also assemble in larger numbers, showing up fleetingly in particle colliders in groups of four (see Synopsis: New Tetraquark Spotted in Electron-Positron Collisions) or five (see Synopsis: Pentaquark Discovery Confirmed). Now the Large Hadron Collider beauty (LHCb) Collaboration at CERN’s LHC has discovered two new four-quark particles. The quark compositions and charges of these tetraquarks make them good for testing theoretical models. The LHC recently began its third operational run, but this new result is drawn from data gathered during runs 1 and 2. The LHCb Collaboration analyzed detector tracks left by charged kaons and pions, which are the ultimate products of proton–proton collisions. From these tra...