TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The crystal is a free-standing ammonothermal group III metal nitride crystal. The crystal comprises a group III metal that is gallium, aluminum, indium and/or nitrogen. The threading dislocations within the locally-approximately linear arrays comprise a concentration of 5-105 cm-1 and the pattern has at least one pitch dimension of 5 mu m and 20 mm and regions between the locally-approximately-linear arrays of threading dislocations has a threading dislocation density of 105 cm2 and a stacking-fault concentration of below 103 cm-1. The first large-area surface has: a symmetric x-ray diffraction rocking curve full width at half maximum less than 200 arcsec; an impurity concentration of greater than 1017 cm-3 and an impurity concentration of hydrogen greater than 1015 cm-3 of at least one of lithium, sodium, potassium, and halo as quantified by calibrated secondary ion mass spectrometry; a crystallographic orientation within 5 degrees of the (10-10) m-plane or (0001)+c-plane, within 5 degrees of the (000-1)-c-plane or within5 degrees of a semipolar orientation that is (60-6||1), (50-5 plus minus 1), (40-4 plus minus 1), (30-3 plus minus 1), (50-5 plus minus 2), (70-7 plus minus 3), (20-2 plus minus 1), (30-3 plus minus 2), (40-4 plus minus 3), (50-5 plus minus 4), (10-1 plus minus ), (10-1 plus minus 2), (10-1 plus minus 3), (21-3 plus minus 1) or (30-3 plus minus 4); impurity concentrations of oxygen, hydrogen, and at least one of fluorine and chlorine at 1x 1016 cm-3-1x 1019 cm-3, 1x 1016 cm-3-2x 1019 cm-3, and 1x 1015 cm-3-1x 1019 cm-3; and impurity concentrations of oxygen, hydrogen and at least one of sodium and potassium at 1x 1016 cm-3-1x 1019 cm-3, 1x 1016 cm-3-2x 1019 cm-3, and 3x 1015 cm-3-1x 1018 cm-3. The threading dislocation density and the stacking fault concentration are determined by etching the first large-area surface in a solution comprising at least one of phosphoric acid, phosphoric acid that is conditioned by prolonged heat treatment forms polyphosphoric acid, sulfuric acid, or in a molten flux comprising at least one of sodium hydroxide or potassium hydroxide at 100-500 degrees C for 5 minutes and 5 hours, where the temperature and the time are selected to cause formation of etch pits with diameters of 1-25 mu m. The pattern is two-dimensional hexagonal, square, rectangular, trapezoidal, triangular, or one-dimensional linear. The locally-approximately-linear arrays are oriented within 5 degrees of a crystallographic plane that is (10-10), (11-20) or (000 plus minus 1), and a projection of the crystallographic plane on the large-area surface. The pattern has a pitch dimension of 200 mu m to 5 mm. The linear concentration of the threading dislocations in the pattern is less than 1x 103 cm-1. The first large area surface has overall dislocation density below 105 cm-2, and the dislocation density within the regions between the locally-approximately-linear arrays of threading dislocations is below 104 cm-2. The stacking fault concentration is below 1 cm-1. The crystal further comprises a second large area surface that is substantially parallel to the first large area surface. The thickness between the first large area surface and the second large area surface is 0.1-1 mm, by a total thickness variation of less than 10 mu m, and by a macroscopic bow less than 50 mu m. The impurity concentration of at least one of lithium, sodium, potassium and halo is greater than 1016 cm-3 or greater than 1015 cm-3 as quantified by calibrated secondary ion mass spectrometry. The impurity concentration of hydrogen is greater than 1018 cm-3 or greater than 1017 cm-3. The ratio of the impurity concentration of hydrogen to an impurity concentration of oxygen is 1.1-100. The first large-area surface comprises regions in which the concentration of threading dislocations varies periodically by at least 2, preferably 10 in at least one direction, where a period of the variation is 5 mu m and 20 mm, preferably 200 mu m and 5 mm. EXAMPLE - No suitable example given.