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This paper reports for the first time on the new laminar quaternary orthorhombic heterometallic quaternary tellurides Sr<i>Ln</i>CuTe₃, the fabrication of which has been a challenge until this work. Data on the crystal structure of tellurides complete the series of quaternary strontium chalcogenides Sr<i>Ln</i>Cu<i>Ch</i>₃ (<i>Ch</i> = S, Se, Te). Single crystals of the compounds were synthesized from the elements by the halogenide-flux method at 1070 K. The compounds are crystallizing in two space groups <i>Pnma</i> (<i>Ln</i> = Sm, Gd and Tb) and <i>Cmcm</i> (<i>Ln</i> = Dy–Tm and Lu). For SrSmCuTe₃ (<i>a</i> = 11.4592(7), <i>b</i> = 4.3706(3), <i>c</i> = 14.4425(9) Å, space group: <i>Pnma</i>) with the largest lanthanoid cation, Sr²⁺ shows <i>C.N.</i> = 7, whereas Sm³⁺ reveals a diminished coordination number <i>C.N.</i> = 6. For SrLuCuTe₃ (<i>a</i> = 4.3064(3), <i>b</i> = 14.3879(9), <i>c</i> = 11.1408(7) Å, space group: <i>Cmcm</i>) with the smallest lanthanoid cation, coordination numbers of six are realized for both high-charged cations (Sr²⁺ and Lu³⁺: <i>C.N.</i> = 6). The cations Sr²⁺, <i>Ln</i>³⁺, Cu⁺ each take independent positions. The structures are built by distorted [CuTe₄]^7– tetrahedra, forming the infinite chains <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mrow><mrow><mmultiscripts><mo stretchy="false">{</mo><mo>∞</mo><mn>1</mn></mmultiscripts><mrow><msup><mrow><mrow><mo stretchy="false">[</mo><mrow><mi>Cu</mi><msubsup><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>1</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>1</mn><mo>/</mo><mn>1</mn></mrow><mi mathvariant="normal">t</mi></msubsup><msubsup><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>2</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>1</mn><mo>/</mo><mn>1</mn></mrow><mi mathvariant="normal">t</mi></msubsup><msubsup><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>3</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow><mi mathvariant="normal">e</mi></msubsup></mrow><mo stretchy="false">]</mo></mrow></mrow><mrow><mn>5</mn><mo>−</mo></mrow></msup></mrow><mo stretchy="false">}</mo></mrow></mrow></mrow></semantics></math></inline-formula> along [010] in Sr<i>Ln</i>CuTe₃ (<i>Ln</i> = Sm, Gd and Tb) and [100] in Sr<i>Ln</i>CuTe₃ (<i>Ln</i> = Dy–Tm and Lu). The distortion of the polyhedra [CuTe₄]^7– was compared for the whole series Sr<i>Ln</i>CuTe₃ by means of τ₄-descriptor for the four coordinating Te^2– anions, which revealed a decrease in the degree of distortion with a decreasing radius at <i>Ln</i>³⁺. The distorted octahedra [<i>Ln</i>Te₆]^9– form layers <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mrow><mrow><mmultiscripts><mo stretchy="false">{</mo><mo>∞</mo><mn>2</mn></mmultiscripts><mrow><msup><mrow><mrow><mo stretchy="false">[</mo><mrow><mi>L</mi><mi>n</mi><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>1</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow></msub><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>2</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow></msub><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>3</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow></msub></mrow><mo stretchy="false">]</mo></mrow></mrow><mrow><mn>3</mn><mo>−</mo></mrow></msup></mrow><mo stretchy="false">}</mo></mrow></mrow></mrow></semantics></math></inline-formula>. The distorted octahedra and tetrahedra fuse to form parallel layers <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mrow><mrow><mmultiscripts><mo stretchy="false">{</mo><mo>∞</mo><mn>2</mn></mmultiscripts><mrow><msup><mrow><mrow><mo stretchy="false">[</mo><mrow><mi>Cu</mi><mi>L</mi><mi>n</mi><msub><mrow><mi>Te</mi></mrow><mn>3</mn></msub></mrow><mo stretchy="false">]</mo></mrow></mrow><mrow><mn>2</mn><mo>−</mo></mrow></msup></mrow><mo stretchy="false">}</mo></mrow></mrow></mrow></semantics></math></inline-formula> and between them, the Sr²⁺ cations providing three-dimensionality of the structure are located. In the Sr<i>Ln</i>CuTe₃ (<i>Ln</i> = Sm, Gd and Tb) structures, the Sr²⁺ cations center capped the trigonal prisms [SrTe₆₊₁]¹²⁻, united in infinite chains <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mrow><mrow><mmultiscripts><mo stretchy="false">{</mo><mo>∞</mo><mn>1</mn></mmultiscripts><mrow><msup><mrow><mrow><mo stretchy="false">[</mo><mrow><mi>Sr</mi><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>1</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow></msub><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>2</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>3</mn><mo>/</mo><mn>3</mn></mrow></msub><msub><mrow><mrow><mo>(</mo><mrow><mi>Te</mi><mn>3</mn></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>/</mo><mn>2</mn></mrow></msub></mrow><mo stretchy="false">]</mo></mrow></mrow><mrow><mn>4</mn><mo>−</mo></mrow></msup></mrow><mo stretchy="false">}</mo></mrow></mrow></mrow></semantics></math></inline-formula> along the [100] direction. The domains of existence of the Ba₂MnS₃, BaLaCuS₃, Eu₂CuS₃ and KZrCuS₃ structure types are defined in the series of orthorhombic chalcogenides Sr<i>Ln</i>Cu<i>Ch</i>₃ (<i>Ch</i> = S, Se and Te). The tellurides Sr<i>Ln</i>CuTe₃ (<i>Ln</i> = Tb–Er) of both structure types in the temperature range from 2 up to 300 K are paramagnetic, without showing clear signs of a magnetic phase transition.