Figure 1.
Location of the abandoned tailings studied in this work, produced by the mining activity in the Taxco district. Due to their size, the Fraile tailings are those that have been most studied [
23,
27], but little work has been made up to this date to characterize the smaller tailings as Remedios and Xochula. Orange oval in the upper left-hand figure delimits the studied area.
Figure 1.
Location of the abandoned tailings studied in this work, produced by the mining activity in the Taxco district. Due to their size, the Fraile tailings are those that have been most studied [
23,
27], but little work has been made up to this date to characterize the smaller tailings as Remedios and Xochula. Orange oval in the upper left-hand figure delimits the studied area.
Figure 2.
Field photographs of the Xochula tailings. (A) Appearance of the JH-38 sample with hydrated iron sulfates. (B) Sample JH-03 shows the field characteristics that generally present the materials without hydrated iron sulfates. (C) The gutters made at one end of the deposits are highlighted by the draining of the water from the surface toward the lower parts. The formation of structures of fibrous appearance in the walls of the channels. (D) Superficial view of the Xochula deposit, the presence of vegetation, and the formation of soils in some portions can be appreciated. (E,F) Views of two walls of the tailings highlight the presence of whitish colorations with efflorescent salts on both sides.
Figure 2.
Field photographs of the Xochula tailings. (A) Appearance of the JH-38 sample with hydrated iron sulfates. (B) Sample JH-03 shows the field characteristics that generally present the materials without hydrated iron sulfates. (C) The gutters made at one end of the deposits are highlighted by the draining of the water from the surface toward the lower parts. The formation of structures of fibrous appearance in the walls of the channels. (D) Superficial view of the Xochula deposit, the presence of vegetation, and the formation of soils in some portions can be appreciated. (E,F) Views of two walls of the tailings highlight the presence of whitish colorations with efflorescent salts on both sides.
Figure 3.
Field photographs of the Remedios tailings. (A–C) Photographs of samples containing iron hydrated sulfates; the macroscopic aspect of salts and efflorescences are highlighted. (D) Image of sample JT-33 located on the surface of the tailings shows the general macroscopic characteristics of materials that do not contain hydrated iron sulfates. (E,F) are panoramic views of the deposit both on the surface and on the wall.
Figure 3.
Field photographs of the Remedios tailings. (A–C) Photographs of samples containing iron hydrated sulfates; the macroscopic aspect of salts and efflorescences are highlighted. (D) Image of sample JT-33 located on the surface of the tailings shows the general macroscopic characteristics of materials that do not contain hydrated iron sulfates. (E,F) are panoramic views of the deposit both on the surface and on the wall.
Figure 4.
Groups established during the application of the analysis by infrared spectroscopy in the samples of the Xochula (JH) tailings and Remedios (JT) tailings. To facilitate the comparison with the minerals reported by other authors [
33,
35], the different bands (vertical lines) of the most important phases identified by X-ray diffraction were introduced. The first group of samples (green) is characterized by the presence of a very flat spectrum, in which only a small peak near 1850 nm stands out, coinciding with a characteristic band of jarosite mineral. This group is the most abundant and is also characterized by the absence of soluble iron sulfates. The second group (blue) is characterized by the presence of two important bands at 1850 nm and 1400 nm (H
2O + OH). For these spectra, in the zone ranging from 2100 to 2300 nm, a single broad band appears, which corresponds mainly to the Fe–OH bond. The third group (brown) displays the same absorption bands as the samples of the second group, but it is characterized by the presence of two bands in the zone between 2100 and 2400 nm, indicating the presence of two types of bonds between OH and metal.
Figure 4.
Groups established during the application of the analysis by infrared spectroscopy in the samples of the Xochula (JH) tailings and Remedios (JT) tailings. To facilitate the comparison with the minerals reported by other authors [
33,
35], the different bands (vertical lines) of the most important phases identified by X-ray diffraction were introduced. The first group of samples (green) is characterized by the presence of a very flat spectrum, in which only a small peak near 1850 nm stands out, coinciding with a characteristic band of jarosite mineral. This group is the most abundant and is also characterized by the absence of soluble iron sulfates. The second group (blue) is characterized by the presence of two important bands at 1850 nm and 1400 nm (H
2O + OH). For these spectra, in the zone ranging from 2100 to 2300 nm, a single broad band appears, which corresponds mainly to the Fe–OH bond. The third group (brown) displays the same absorption bands as the samples of the second group, but it is characterized by the presence of two bands in the zone between 2100 and 2400 nm, indicating the presence of two types of bonds between OH and metal.
Figure 5.
Characteristic short-wave infrared spectroscopy (SWIR) absorption spectra of some iron-bearing sulfates found at Taxco tailings. Reflectance spectra of (A) rozenite, (B) copiapite, (C) jarosite, and (D) hexahydrite, compared with digitalized literature spectra (Velasco et al., 2005; Cloutis et al., 2006). In general, only when the sample has more than 25% of the phase can a good correlation be observed.
Figure 5.
Characteristic short-wave infrared spectroscopy (SWIR) absorption spectra of some iron-bearing sulfates found at Taxco tailings. Reflectance spectra of (A) rozenite, (B) copiapite, (C) jarosite, and (D) hexahydrite, compared with digitalized literature spectra (Velasco et al., 2005; Cloutis et al., 2006). In general, only when the sample has more than 25% of the phase can a good correlation be observed.
Figure 6.
Representative XRD patterns from each of the three sample groups for Xochula (JH) tailings and Remedios (JT) tailings. The first group (blue) is characterized by the presence of primary minerals (mainly quartz) and phyllosilicates (mainly mica), gypsum, jarosite, and a variable proportion of iron oxides and hydroxides. The second group of samples (green) has a predominance of secondary hydrated sulfates with reduced iron (Fe2+). Samples from that group may also contain jarosite, gypsum, iron, and/or quartz oxides and hydroxides in varying proportions. The third group of samples (brown) has a predominance of hydrated tertiary iron sulfates or a mixture of secondary and tertiary sulfates (Fe2+ + Fe3+). Samples from that group may also contain quartz, jarosite, gypsum, iron oxides, and hydroxides in varying proportions. Co: copiapite; Ch: chlorite; Hex: hexahydrite; FeCo: ferrocopiapite; Fl: fluorite; Goe: goethite; Gy: gypsum; Hem: hematite; Ja: jarosite; Q: quartz; Mel: melanterite; Roz: rozenite; Szo: szomolnokite.
Figure 6.
Representative XRD patterns from each of the three sample groups for Xochula (JH) tailings and Remedios (JT) tailings. The first group (blue) is characterized by the presence of primary minerals (mainly quartz) and phyllosilicates (mainly mica), gypsum, jarosite, and a variable proportion of iron oxides and hydroxides. The second group of samples (green) has a predominance of secondary hydrated sulfates with reduced iron (Fe2+). Samples from that group may also contain jarosite, gypsum, iron, and/or quartz oxides and hydroxides in varying proportions. The third group of samples (brown) has a predominance of hydrated tertiary iron sulfates or a mixture of secondary and tertiary sulfates (Fe2+ + Fe3+). Samples from that group may also contain quartz, jarosite, gypsum, iron oxides, and hydroxides in varying proportions. Co: copiapite; Ch: chlorite; Hex: hexahydrite; FeCo: ferrocopiapite; Fl: fluorite; Goe: goethite; Gy: gypsum; Hem: hematite; Ja: jarosite; Q: quartz; Mel: melanterite; Roz: rozenite; Szo: szomolnokite.
Figure 7.
Example of quantification of crystalline phases using XRD and the Rietveld refinement method for sample JT11 (JT-IDRX).
Figure 7.
Example of quantification of crystalline phases using XRD and the Rietveld refinement method for sample JT11 (JT-IDRX).
Figure 8.
Microphotographs of samples with efflorescence. JH: Xochula; JT: Remedios. (a) Sample JH41, prismatic gypsum crystals; (b) Sample JH02, general aspect of the sample with different types of sulfates (mainly jarosite with anhedral crystals and tabular copiapite); (c) Sample JH48, tabular copiapite crystals; (d) Sample JH48, gypsum, jarosite, and clay minerals (central part), with tabular copiapite crystals at the external part; (e) Sample JT03, general appearance of the sample. It is observed that the sample is formed by an irregular mixture of different types of sulfates mixed with residues of the primary material; (f) Sample JT03, aggregate of copiapite crystals. In scale bar um = µm.
Figure 8.
Microphotographs of samples with efflorescence. JH: Xochula; JT: Remedios. (a) Sample JH41, prismatic gypsum crystals; (b) Sample JH02, general aspect of the sample with different types of sulfates (mainly jarosite with anhedral crystals and tabular copiapite); (c) Sample JH48, tabular copiapite crystals; (d) Sample JH48, gypsum, jarosite, and clay minerals (central part), with tabular copiapite crystals at the external part; (e) Sample JT03, general appearance of the sample. It is observed that the sample is formed by an irregular mixture of different types of sulfates mixed with residues of the primary material; (f) Sample JT03, aggregate of copiapite crystals. In scale bar um = µm.
Figure 9.
Contour map calculated from the quantitative data obtained using X-ray diffraction and the Rietveld method for Xochula (JH)) tailings. The groups considered are: primary minerals (pyrite, fluorite, calcite, and feldspars) in brown color, phyllosilicates (micas, smectites, kaolinite, chlorite) in light green color, secondary hydrated sulfates (Fe2+) in dark green color, tertiary hydrated sulfates (Fe3+) in blue color, alunite group minerals (mainly jarosite) in cyan color, gypsum in purple color, and iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite) in red color. The black line represents the outline of the tailings (superficial and lateral views).
Figure 9.
Contour map calculated from the quantitative data obtained using X-ray diffraction and the Rietveld method for Xochula (JH)) tailings. The groups considered are: primary minerals (pyrite, fluorite, calcite, and feldspars) in brown color, phyllosilicates (micas, smectites, kaolinite, chlorite) in light green color, secondary hydrated sulfates (Fe2+) in dark green color, tertiary hydrated sulfates (Fe3+) in blue color, alunite group minerals (mainly jarosite) in cyan color, gypsum in purple color, and iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite) in red color. The black line represents the outline of the tailings (superficial and lateral views).
Figure 10.
Contour map calculated from the quantitative data obtained using X-ray diffraction and the Rietveld method for Remedios (JT) tailings. The groups considered are: iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite) in red color, phyllosilicates (micas, smectites, kaolinite, and chlorite) in light green color, secondary hydrated sulfates (Fe2+) in dark green color, tertiary hydrated sulfates (Fe3+) in blue color, alunite group minerals (mainly jarosite) in cyan color, gypsum in purple color. The black line represents the outline of the tailings (superficial view).
Figure 10.
Contour map calculated from the quantitative data obtained using X-ray diffraction and the Rietveld method for Remedios (JT) tailings. The groups considered are: iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite) in red color, phyllosilicates (micas, smectites, kaolinite, and chlorite) in light green color, secondary hydrated sulfates (Fe2+) in dark green color, tertiary hydrated sulfates (Fe3+) in blue color, alunite group minerals (mainly jarosite) in cyan color, gypsum in purple color. The black line represents the outline of the tailings (superficial view).
Figure 11.
Dendrogram based on the quantitative X-ray diffraction data calculated with the Rietveld method. The groups considered are: primary minerals (pyrite, fluorite, calcite, and feldspars), secondary hydrated sulfates (Fe2+), tertiary hydrated sulfates (Fe3+), alunite group minerals (mainly jarosite), phyllosilicates (micas, smectites, kaolinite, and chlorite), gypsum, iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite). (A) Xochula (JH) and (B) Remedios (JT).
Figure 11.
Dendrogram based on the quantitative X-ray diffraction data calculated with the Rietveld method. The groups considered are: primary minerals (pyrite, fluorite, calcite, and feldspars), secondary hydrated sulfates (Fe2+), tertiary hydrated sulfates (Fe3+), alunite group minerals (mainly jarosite), phyllosilicates (micas, smectites, kaolinite, and chlorite), gypsum, iron oxides and hydroxides (schwertmannite, ferrihydrite, hematite, and goethite). (A) Xochula (JH) and (B) Remedios (JT).
Figure 12.
Stages of mineral (sulfates and oxides) precipitation formed mainly by oxidation, hydration, and evaporation.
Figure 12.
Stages of mineral (sulfates and oxides) precipitation formed mainly by oxidation, hydration, and evaporation.
Table 1.
Physical description of samples from the superficial (JH-01 to JH-36) and lateral (JH-37 to JH-41) parts of Xochula Tailings.
Table 1.
Physical description of samples from the superficial (JH-01 to JH-36) and lateral (JH-37 to JH-41) parts of Xochula Tailings.
Sample | Origin | Coloration | Description |
---|
JH-01 | Tailings | Yellowish orange | Very fine grain efflorescent salts |
JH-02 | Tailings | Pale yellow | Soft crust without vegetation |
JH-03 | Tailings | Yellowish orange | Material with fibrous texture |
JH-04 | Soil | Yellowish brown and bluish | Fine grain with vegetation |
JH-05 | Tailings | Brownish-yellowish orange | Very fine grain without efflorescence |
JH-5-1 | Tailings and crust | Intense orange and violet red | Consolidated crust |
JH-06 | Soil | Orange brown | Fine grain with vegetation |
JH-07 | Soil | Yellowish brown | Fine grain with vegetation |
JH-08 | Soil | Brown | Consolidated material without vegetation |
JH-09 | Soil | Yellowish brown | Fine grain with vegetation |
JH-10 | Soil | Yellowish brown | Fine grain with vegetation |
JH-11 | Soil | Brown | Fine grain with vegetation |
JH-12 | Soil | Yellowish brown | Fine grain with vegetation |
JH-13 | Soil | Yellowish reddish brown | Fine grain with vegetation |
JH-14 | Soil | Orange brown | Fine grain with vegetation |
JH-15 | Soil | Yellowish brown | Fine grain with vegetation |
JH-16 | Soil | Dark yellowish brown | Fine grain with vegetation |
JH-17 | Tailings | Intense orange | Crust without vegetation |
JH-18 | Soil | Yellowish brown | Fine grain with vegetation |
JH-19 | Soil | Yellowish brown | Fine grain with vegetation |
JH-20 | Tailings | Yellowish white | Very fine grain efflorescent salts |
JH-21 | Tailings | Bright yellow orange | Loose material without vegetation |
JH-22 | Tailings | Dark Yellowish brown | Consolidated without vegetation |
JH-23 | Soil | Light yellowish brown | Fine grain with vegetation |
JH-24 | Soil | Yellowish brown | Fine grain with vegetation |
JH-25 | Soil | Orange-reddish brown | Fine grain with vegetation |
JH-26 | Soil | Yellowish brown | Fine grain with vegetation |
JH-27 | Soil | Yellowish brown | Fine grain with vegetation |
JH-28 | Soil | Yellowish-orange brown | Fine grain with vegetation |
JH-29 | Soil | Yellowish brown | Fine grain with vegetation |
JH-30 | Tailings | Intense orange | Fine grain without vegetation |
JH-31 | Tailings | Yellowish white | Very fine grain efflorescent salts |
JH-32 | Tailings | Yellowish white | Very fine grain efflorescent salts |
JH-33 | Tailings | Intense orange | Loose sandy material |
JH-34 | Tailings | Intense orange and yellow | Loose sandy material |
JH-35 | Tailings | Intense orange | Loose sandy material |
JH-36 | Tailings | Reddish violet and orange | Slightly hardened scab |
JH-37 | Tailings | Yellowish white | Very fine grain efflorescent salts |
JH-38 | Tailings | Whitish | Very fine grain efflorescent salts |
JH-39 | Tailings | White orange | Massive, fine-grained efflorescent salts |
JH-40 | Tailings | Pink white | Very fine grain efflorescent salts |
JH-41 | Tailings | Gray bluish lead | Consolidated material with fibrous texture |
Table 2.
Physical description of samples from the superficial (JT-01 to JT-47) and lateral (JT-03, JT-04, JT-05, JT-06, JT-16, JT-44, JT-45, JT-46, JT-48 and JT-49) parts of Remedios Tailings.
Table 2.
Physical description of samples from the superficial (JT-01 to JT-47) and lateral (JT-03, JT-04, JT-05, JT-06, JT-16, JT-44, JT-45, JT-46, JT-48 and JT-49) parts of Remedios Tailings.
Sample | Origin | Coloration | Description |
---|
JT-01 | Tailings | Loose sandy material | Loose sandy material |
JT-02 | Tailings | Yellowish brown | Material with fibrous texture |
JT-07 | Tailings | Violet gray | Loose sandy material |
JT-08 | Tailings | Orange brown | Very fine grain efflorescent salts |
JT-09 | Tailings | Greenish yellow | Very fine grain efflorescent salts |
JT-10 | Tailings | Orange brown | Loose sandy material |
JT-11 | Tailings | Orange red | Loose sandy material |
JT-12 | Tailings | Intense orange and yellow | Loose sandy material |
JT-13 | Tailings | Yellowish orange | Weakly consolidated |
JT-14 | Tailings | Pink violet | Slightly hardened crust |
JT-15 | Tailings | Yellowish brown | Loose sandy material |
JT-17 | Tailings | Red brown | Slightly hardened scab |
JT-18 | Tailings | Red brown | Slightly hardened scab |
JT-19 | Tailings | Pink violet | Slightly hardened scab |
JT-20 | Tailings | Dark brown violet | Slightly hardened scab |
JT-21 | Tailings | Yellowish brown | Crust with disease cracks |
JT-22 | Tailings | Yellowish orange | Very fine grain efflorescent salts |
JT-23 | Tailings | Orange-red brown | Crust with disease cracks |
JT-24 | Tailings | Intense orange brown | Soft crust with efflorescence of fine particle size |
JT-25 | Tailings | Yellowish brown | Loose sandy material |
JT-26 | Tailings | Orange and greenish yellow | Loose sandy material |
JT-27 | Tailings | Amarillo greenish | Very fine grain efflorescent salts |
JT-28 | Tailings | Intense violet | Loose sandy material |
JT-29 | Tailings | Yellowish orange | Slightly hardened crust |
JT-30 | Tailings | Intense orange brown | Loose sandy material |
JT-31 | Tailings | Intense orange | Crust lightly hardened |
JT-32 | Tailings | Bright yellow | Loose sandy material |
JT-33 | Tailings | Bright orange | Very fine grain efflorescent salts |
JT-34 | Soil | Black | Crust lightly hardened |
JT-35 | Tailings | White orange | Very fine grain efflorescent salts |
JT-36 | Tailings | Bright violet | Very fine grain efflorescent salts |
JT-37 | Tailings | Reddish brown pink | Crust lightly hardened |
JT-38 | Tailings | Yellowish orange | Loose sandy material |
JT-39 | Tailings | Bright yellow | Stratified layers and crusts |
JT-40 | Tailings | Reddish brown | Loose sandy material |
JT-41 | Tailings | Yellowish orange | Stratified layers and crusts |
JT-42 | Tailings | Bright brown | Crust lightly hardened |
JT-43 | Tailings | Yellowish orange | Crust lightly hardened |
JT-47 | Tailings | Orange white | Very fine grain and massive efflorescent salts |
JT-03 | Tailings | Bright orange and blue | Very fine grain and massive efflorescent salts |
JT-04 | Tailings | Whitish | Very fine grain and massive efflorescent salts |
JT-05 | Tailings | Bright greenish yellow | Very fine grain and massive efflorescent salts |
JT-06 | Tailings | Bright orange | Very fine grain and massive efflorescent salts |
JT-16 | Tailings | Yellowish white | Stratified layers and crusts |
JT-44 | Tailings | Yellowish white | Very fine grain and massive efflorescent salts |
JT-45 | Tailings | White | Very fine grain and massive efflorescent salts |
JT-46 | Tailings | Bright orange | Very fine grain and massive efflorescent salts |
JT-48 | Tailings | Bright brown | Weakly hardened scab |
JT-49 | Tailings | Bright white brown | Very fine grain and massive efflorescent salts |
Table 3.
Relevant data from the diffractometer used during measurement and Rietveld refinement.
Table 3.
Relevant data from the diffractometer used during measurement and Rietveld refinement.
Parameter | Value | Parameter | Value |
---|
Geometry | Bragg-Brentano | Divergence slit | ½° |
Goniometer radius | 240 mm | Incident antiscatter slit | 1° |
Radiation source | CuKα and CoKα | Reflected antiscatter slit | 7.5° |
Generator | 45 kV, 40 mA | Soller slits | 0.04 rad |
Tube | Long Fine Focus | Detector | Solid state (PIXcel3D) |
Monochromator | None | Step size | 0.003° (2θ) |
Filter | Nickel (Cu) and Iron (Co) | Integration time | 30 s |
Incident beam optics | Parallel mirror (Göbel) | Spinning | 15 rpm |
Table 4.
Table with the non-primary minerals found in the studied efflorescences of Xochula (JH) and Remedios (JT) tailings.
Table 4.
Table with the non-primary minerals found in the studied efflorescences of Xochula (JH) and Remedios (JT) tailings.
Mineral Name | Abbr. | Chemical Formula | Group | XRD Pattern Ref. | Characteristic XRD Peaks (Å) |
---|
Botryogen | Bot | MgFe3+(SO4)2(OH)·7(H2O) | Iron and Mg hydroxysulfate | ICSD 980034682 | 6.36 | 8.96 | 5.52 |
Epsomite | Ep | MgSO4·7(H2O) | Hydrous Mg sulfate | ICSD 980029384 | 4.22 | 4.21 | 5.36 |
Halotrichite | Hal | Fe2+Al2(SO4)4·22(H2O) | Hydrous Fe and Al sulfate | ICSD 980096598 | 4.80 | 15.84 | 4.95 |
Hexahydrite | Hex | MgSO4·6(H2O) | Hydrous Mg sulfate | ICSD 980016546 | 4.36 | 5.45 | 4.03 |
Hohmannite | Hoh | Fe3+2(SO4)2(OH)2·7(H2O) | Iron hydroxysulfate | ICSD 980037328 | 7.96 | 8.73 | 10.42 |
Fibroferrite | Fi | Fe3+(SO4)(OH)·5(H2O) | Iron hydroxysulfate | ICSD 980100721 | 12.08 | 4.07 | 3.45 |
Gunningite | Gun | (Zn, Mn2+)SO4·H2O | Hydrous Zn and Mn sulfate | ICSD 980071348 | 4.40 | 4.76 | 3.05 |
Kieserite | Kie | MgSO4·H2O | Hydrous Mg sulfate | ICSD 980015924 | 4.79 | 3.40 | 3.36 |
Melanterite | Me | FeSO4·7H2O | Hydrous Fe sulfate | ICSD 980016589 | 4.90 | 3.77 | 4.87 |
Rostite | Ros | Al(SO4)(OH)·5H2O | Hydroxysulfate | ICDD 000421427 | 4.25 | 4.18 | 3.90 |
Rozenite | Roz | FeSO4·4H2O | Hydrous Fe sulfate | ICSD 980023914 | 5.47 | 4.50 | 3.98 |
Starkeyite | Stk | MgSO4·4(H2O) | Hydrous Mg sulfate | ICDD 010721096 | 4.47 | 5.43 | 3.95 |
Szomolnokite | Szo | Fe2+SO4·(H2O) | Hydrous Fe sulfate | ICSD 980027098 | 3.44 | 3.11 | 4.86 |
Copiapite | Cop | Fe2+Fe3+4(SO4)6(OH)2 20(H2O) | Hydroxysulfate | ICDD 000110395 | 10.5 | 6.87 | 3.43 |
Coquimbite | Coq | Fe3+2(SO4)3·9(H2O) | Hydrous Fe sulfate | ICDD 010802836 | 8.27 | 9.45 | 3.36 |
Alunite | Al | KAl3(SO4)2(OH)6 | Hydrous sulfate of K and Al | ICSD 980012106 | 5.40 | 7.37 | 10.81 |
Jarosite | Jar | KFe3+3(SO4)2(OH)6 | Hydrous sulfate of K and Fe | ICSD 980157717 | 3.08 | 5.10 | 3.11 |
Beudantite | Beu | PbFe3(AsO4)(SO4)(OH)6 | Hydrous arsenate of Pb and Fe | ICSD 980067455 | 3.07 | 5.94 | 3.66 |
Pb-Jarosite | PbJar | Pb0.5Fe3+3(SO4)2(OH)6 | Hydrous sulfate of Pb and Fe | ICSD 980169961 | 3.07 | 5.93 | 2.25 |
Gypsum | Gy | CaSO4·2H2O | Calcium sulfate dihydrate | ICSD 980161622 | 7.59 | 4.28 | 2.87 |
Ferrihydrite | Ferri | Fe3+2O3·0.5(H2O) | Hydrous ferric oxyhydroxide | ICSD 980056287 | 1.15 | 1.02 | 0.90 |
Goethite | Goe | Fe+3O(OH) | Iron oxyhydroxide | ICDD 010755065 | 4.18 | 2.45 | 3.88 |
Hematite | Hem | Fe2O3 | Iron oxide | ICDD 010715088 | 2.70 | 2.52 | 3.68 |
Schwertmann. | Schw | Fe3+16O16(OH)12(SO4)2 | Iron oxyhydroxysulfate | ICSD 980169971 | 2.55 | 3.39 | 4.86 |
Table 5.
Major element analysis from three samples of Remedios tailings. Concentrations in wt %. All detection limits 0.01%, except Mn, 0.001%. LOI: loss on ignition.
Table 5.
Major element analysis from three samples of Remedios tailings. Concentrations in wt %. All detection limits 0.01%, except Mn, 0.001%. LOI: loss on ignition.
Sample | SiO2 | Al2O3 | Fe2O3(T) | MnO | MgO | CaO | Na2O | K2O | TiO2 | P2O5 | LOI | Total |
---|
JT-05 | 20.47 | 1.92 | 26.23 | 0.222 | 0.24 | 3.46 | 0.02 | 0.34 | 0.071 | 0.03 | 43.25 | 96.25 |
JT-03 | 20.80 | 1.33 | 25.69 | 0.585 | 0.26 | 4.70 | 0.01 | 0.24 | 0.040 | 0.02 | 38.11 | 91.78 |
JT-48 | 27.51 | 1.43 | 25.89 | 0.486 | 0.23 | 6.47 | 0.02 | 0.38 | 0.103 | 0.03 | 29.38 | 91.92 |
Table 6.
Induced coupled plasma mass spectrometry (ICP–MS) analysis of some important trace elements from three samples of Remedios tailings. Concentrations in µg g
−1 (ppm). Detection limits: Cu (10), Zn (30), As (5), Sn (1), Sb (0.2), W (10), Pb (30). RBV: Regional background values [
23]; NOM-141: NOM-141-SEMARNAT-2003 [
42].
Table 6.
Induced coupled plasma mass spectrometry (ICP–MS) analysis of some important trace elements from three samples of Remedios tailings. Concentrations in µg g
−1 (ppm). Detection limits: Cu (10), Zn (30), As (5), Sn (1), Sb (0.2), W (10), Pb (30). RBV: Regional background values [
23]; NOM-141: NOM-141-SEMARNAT-2003 [
42].
Sample | Cu | Zn | As | Sn | Sb | W | Pb |
---|
JT-05 | 850 | 2980 | 569 | 815 | 37.6 | 45.8 | 1260 |
JT-03 | 880 | 9000 | 453 | 573 | 48.6 | 33.6 | 4730 |
JT-48 | 980 | 6920 | 519 | >1000 | 59.5 | 58.8 | 2830 |
RBV | 25 | 64 | 30 | - | 9.0 | - | 26 |
NOM-141 | 100 | 100 | 20 | - | - | - | 100 |