The new [(Zr6B)Cl-11-xI(2+x)] phase (with 0 less than or equal to x less than or equal to 6) is obtained from reactions of ZrI4, ZrCl4, and elemental Zr and B for 2-4 weeks in sealed Ta tubing at 800-850 degreesC. Single crystals of [(Zr6B)Cl6.44(7)I6.56] have been characterized by X-ray diffraction at room temperature (orthorhombic Pbcn, Z = 4, a = 12.365(2) Angstrom, b = 15.485(3) Angstrom, c = 13.405(2) Angstrom). This structure contains zigzag chains of boron-centered (Zr6B) octahedra that are interconnected by Cli-i halides. Further three-dimensional connectivity is achieved by Ia-a-a bridges. The noncluster interconnecting two-bonded X-i sites are occupied statistically by a mixture of Cl and I. For each site both positions were resolved. This structure forms within a phase width of 0 less than or equal to x less than or equal to 6 at temperatures between 800 and 850 degreesC. Crystals of this phase appear to be always multiply twinned.