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[en] A lead borate with the composition Pb_6B_1_2O_2_1(OH)_6 was synthesized through a hydrothermal synthesis, using lead metaborate in combination with sodium nitrate and potassium nitrate. The compound crystallizes in the trigonal, non-centrosymmetric space group P3_2 (no. 145) with the lattice parameters a = 1176.0(4), c = 1333.0(4) pm, and V = 0.1596(2) nm"3. Interestingly, the data of Pb_6B_1_2O_2_1(OH)_6 correct the structure of a literature known lead borate with the composition ''Pb_6B_1_1O_1_8(OH)_9''. For the latter compound, nearly identical lattice parameters of a = 1176.91(7) and c = 1333.62(12) pm were reported, possessing a crystal structure, in which the localization and refinement of one boron atom was obviously overlooked. The structure of Pb_6B_1_2O_2_1(OH)_6 is built up from trigonal planar BO_3 and tetrahedral BO_4 groups forming complex chains. The Pb"2"+ cations are located between neighboring polyborate chains. The here reported compound Pb_6B_1_2O_2_1(OH)_6 and ''Pb_6B_1_1O_1_8(OH)_9'' were, however, produced under different synthesis conditions. While ''Pb_6B_1_1O_1_8(OH)_9'' was synthesized via a hydrothermal synthesis including ethylenediamine and acetic acid, the here reported lead borate Pb_6B_1_2O_2_1(OH)_6 could be obtained under moderate hydrothermal conditions (240 C) without the addition of organic reagents.