Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja
Mg-calcite and dolomite from the white marble Krečana-Venčac ore deposit, Part I: X-ray investigations
Апстракт
With the X-ray powder diffraction analysis there were indiced powder diffraction patterns and determined qualitative, semiquantitative sample contents.
Sample-1 contain Mg-calcite (1) (95%), dolomite (4%) and quartz (1%).
Sample-2 contain Mg-calcite (2) (79%), quartz, feldspars, clay minerals and micas, and insignificant dolomite (1,5%). Quartz, feldspars and clay minerals-micas are probably of equally content with about 6-7%. There were calculated following unit cell dimensions:
Mg-calcite (1): ao = 4,966(2)Å, co = 16,96(1)Å; Vo = 362,1(4)Å3; co/ao = 3,415;
dolomite: ao = 4,791(3)Å, co = 15,95(2)Å; Vo = 317,1(4)Å3; co/ao = 3,329;
Mg-calcite (2): ao = 4,9791(9)Å, co = 17,025(5)Å; Vo = 365,5(1)Å3; co/ao = 3,419;
From calculated unit cell dimensions of all of these minerals it can be seen that there were partly exchanging of Ca2+ with Mg2+ and/or Fe2+, which are of smaller ionic radius than Ca2+.
At Mg-calcite (1) 5,14 mol.% CaCO3 exchanged with MgCO3, while at Mg-calc...ite (2) 1,86 mol.%. Difference of 3,28 mol.% is related to the submicroscopic intergrowths and exsolutions of dolomite in Mg-calcite (1), and which were destroyed in Mg-calcite (2). At metamorphic Mg-calcite there did not came to distortion of the octahedra, because there were obtained almost equally MgCO3 contents through ao, co, Vo and co/ao. At dolomite it was established considerable deficit of the CaCO3 component.
Кључне речи:
Krečana-Venčac / metamorphism / X-ray investigations / Mg-calcite / dolomite / unit cell dimensions / MgCO3 content / Mg-calcite composition / dolomite compositionИзвор:
Radovi, 2005, 40, 201-224Издавач:
- Geoinstitut
Институција/група
IHTMTY - JOUR AU - Tančić, Pavle PY - 2005 UR - https://cer.ihtm.bg.ac.rs/handle/123456789/6443 AB - With the X-ray powder diffraction analysis there were indiced powder diffraction patterns and determined qualitative, semiquantitative sample contents. Sample-1 contain Mg-calcite (1) (95%), dolomite (4%) and quartz (1%). Sample-2 contain Mg-calcite (2) (79%), quartz, feldspars, clay minerals and micas, and insignificant dolomite (1,5%). Quartz, feldspars and clay minerals-micas are probably of equally content with about 6-7%. There were calculated following unit cell dimensions: Mg-calcite (1): ao = 4,966(2)Å, co = 16,96(1)Å; Vo = 362,1(4)Å3; co/ao = 3,415; dolomite: ao = 4,791(3)Å, co = 15,95(2)Å; Vo = 317,1(4)Å3; co/ao = 3,329; Mg-calcite (2): ao = 4,9791(9)Å, co = 17,025(5)Å; Vo = 365,5(1)Å3; co/ao = 3,419; From calculated unit cell dimensions of all of these minerals it can be seen that there were partly exchanging of Ca2+ with Mg2+ and/or Fe2+, which are of smaller ionic radius than Ca2+. At Mg-calcite (1) 5,14 mol.% CaCO3 exchanged with MgCO3, while at Mg-calcite (2) 1,86 mol.%. Difference of 3,28 mol.% is related to the submicroscopic intergrowths and exsolutions of dolomite in Mg-calcite (1), and which were destroyed in Mg-calcite (2). At metamorphic Mg-calcite there did not came to distortion of the octahedra, because there were obtained almost equally MgCO3 contents through ao, co, Vo and co/ao. At dolomite it was established considerable deficit of the CaCO3 component. PB - Geoinstitut T2 - Radovi T1 - Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja T1 - Mg-calcite and dolomite from the white marble Krečana-Venčac ore deposit, Part I: X-ray investigations VL - 40 SP - 201 EP - 224 UR - https://hdl.handle.net/21.15107/rcub_cer_6443 ER -
@article{ author = "Tančić, Pavle", year = "2005", abstract = "With the X-ray powder diffraction analysis there were indiced powder diffraction patterns and determined qualitative, semiquantitative sample contents. Sample-1 contain Mg-calcite (1) (95%), dolomite (4%) and quartz (1%). Sample-2 contain Mg-calcite (2) (79%), quartz, feldspars, clay minerals and micas, and insignificant dolomite (1,5%). Quartz, feldspars and clay minerals-micas are probably of equally content with about 6-7%. There were calculated following unit cell dimensions: Mg-calcite (1): ao = 4,966(2)Å, co = 16,96(1)Å; Vo = 362,1(4)Å3; co/ao = 3,415; dolomite: ao = 4,791(3)Å, co = 15,95(2)Å; Vo = 317,1(4)Å3; co/ao = 3,329; Mg-calcite (2): ao = 4,9791(9)Å, co = 17,025(5)Å; Vo = 365,5(1)Å3; co/ao = 3,419; From calculated unit cell dimensions of all of these minerals it can be seen that there were partly exchanging of Ca2+ with Mg2+ and/or Fe2+, which are of smaller ionic radius than Ca2+. At Mg-calcite (1) 5,14 mol.% CaCO3 exchanged with MgCO3, while at Mg-calcite (2) 1,86 mol.%. Difference of 3,28 mol.% is related to the submicroscopic intergrowths and exsolutions of dolomite in Mg-calcite (1), and which were destroyed in Mg-calcite (2). At metamorphic Mg-calcite there did not came to distortion of the octahedra, because there were obtained almost equally MgCO3 contents through ao, co, Vo and co/ao. At dolomite it was established considerable deficit of the CaCO3 component.", publisher = "Geoinstitut", journal = "Radovi", title = "Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja, Mg-calcite and dolomite from the white marble Krečana-Venčac ore deposit, Part I: X-ray investigations", volume = "40", pages = "201-224", url = "https://hdl.handle.net/21.15107/rcub_cer_6443" }
Tančić, P.. (2005). Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja. in Radovi Geoinstitut., 40, 201-224. https://hdl.handle.net/21.15107/rcub_cer_6443
Tančić P. Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja. in Radovi. 2005;40:201-224. https://hdl.handle.net/21.15107/rcub_cer_6443 .
Tančić, Pavle, "Mg-kalcit i dolomit iz belog mermera ležišta Krečana - Venčac, deo I: rendgenska ispitivanja" in Radovi, 40 (2005):201-224, https://hdl.handle.net/21.15107/rcub_cer_6443 .