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Mineralogical Crystallography
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Mineralogical Crystallography

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Mineralogical Crystallography and Biomineralization".

Deadline for manuscript submissions: closed (1 May 2020) | Viewed by 50850

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor

Prof. Dr. Vladislav V. Gurzhiy

E-Mail Website
Guest Editor
Department Crystallography, Institute of Earth Sciences, St. Petersburg State University, University Emb. 7/9, 199034 St. Petersburg, Russia
Interests: crystallography; mineralogy; X-ray diffraction; uranium; inorganic chemistry; radiochemistry
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Crystallography remains for mineralogy one of the main sources of information about natural crystalline substances. A description of mineral species shape is carried out according to the principles of geometric crystallography; the crystal structure of minerals is determined using X-ray crystallography techniques, and physical crystallography approaches allow one to evaluate various properties of minerals, etc. However, the reverse comparison should not be forgotten as well: the crystallography science, in its current form, was born in the course of mineralogical research, long before preparative chemistry received such extensive development. It is worth saying that, even today, investigations of crystallographic characteristics of minerals regularly open up new horizons in materials science, because the possibilities of nature (fascinating chemical diversity; great variation of thermodynamic parameters; and, of course, almost endless processing time) are still not available for reproduction in any of the world's laboratories. This Special Issue is devoted to mineralogical crystallography, the oldest branch of crystallographic science, and aims to combine important surveys covering topics indicated in the keywords below.

We invite you to participate in this Issue and to contribute your research results in the fields of new mineral species discovery, structural studies of minerals and related synthetic materials, crystal chemical overviews of various mineral groups, the evolution of mineral species and their crystal structures, and descriptions of growth processes and the properties of the natural crystalline compounds.

Best regards,
Dr. Vladislav V. Gurzhiy
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Crystals is an international peer-reviewed open access monthly journal published by MDPI.

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Keywords

  • Minerals
  • Crystallography
  • Crystal chemistry
  • X-ray diffraction
  • Crystal structures
  • Crystal growth
  • Mineral evolution

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Related Special Issue

Published Papers (12 papers)

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Editorial

Jump to: Research, Review

3 pages, 179 KiB  
Editorial
Mineralogical Crystallography
by Vladislav V. Gurzhiy
Crystals 2020, 10(9), 805; https://doi.org/10.3390/cryst10090805 - 11 Sep 2020
Cited by 2 | Viewed by 1944
Abstract
Crystallography remains, for mineralogy, one of the main sources of information on natural crystalline substances [...] Full article
(This article belongs to the Special Issue Mineralogical Crystallography)

Research

Jump to: Editorial, Review

18 pages, 25387 KiB  
Article
A Complex Assemblage of Crystal Habits of Pyrite in the Volcanic Hot Springs from Kamchatka, Russia: Implications for the Mineral Signature of Life on Mars
by Min Tang and Yi-Liang Li
Crystals 2020, 10(6), 535; https://doi.org/10.3390/cryst10060535 - 23 Jun 2020
Cited by 3 | Viewed by 4896
Abstract
In this study, the crystal habits of pyrite in the volcanic hot springs from Kamchatka, Russia were surveyed using scanning electron microscopy. Pyrite crystals occur either as single euhedral crystals or aggregates with a wide range of crystal sizes and morphological features. Single [...] Read more.
In this study, the crystal habits of pyrite in the volcanic hot springs from Kamchatka, Russia were surveyed using scanning electron microscopy. Pyrite crystals occur either as single euhedral crystals or aggregates with a wide range of crystal sizes and morphological features. Single euhedral crystals, with their sizes ranging from ~200 nm to ~40 µm, exhibit combinations of cubic {100}, octahedral {111}, and pyritohedral {210} and {310} forms. Heterogeneous geochemical microenvironments and the bacterial activities in the long-lived hot springs have mediated the development and good preservation of the complex pyrite crystal habits: irregular, spherulitic, cubic, or octahedral crystals congregating with clay minerals, and nanocrystals attaching to the surface of larger pyrite crystals and other minerals. Spherulitic pyrite crystals are commonly covered by organic matter-rich thin films. The coexistence of various sizes and morphological features of those pyrite crystals indicates the results of secular interactions between the continuous supply of energy and nutritional elements by the hot springs and the microbial communities. We suggest that, instead of a single mineral with unique crystal habits, the continuous deposition of the same mineral with a complex set of crystal habits results from the ever-changing physicochemical conditions with contributions from microbial mediation. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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14 pages, 2150 KiB  
Article
Crystal Chemistry of Stanfieldite, Ca7M2Mg9(PO4)12 (M = Ca, Mg, Fe2+), a Structural Base of Ca3Mg3(PO4)4 Phosphors
by Sergey N. Britvin, Maria G. Krzhizhanovskaya, Vladimir N. Bocharov and Edita V. Obolonskaya
Crystals 2020, 10(6), 464; https://doi.org/10.3390/cryst10060464 - 1 Jun 2020
Cited by 5 | Viewed by 3010
Abstract
Stanfieldite, natural Ca-Mg-phosphate, is a typical constituent of phosphate-phosphide assemblages in pallasite and mesosiderite meteorites. The synthetic analogue of stanfieldite is used as a crystal matrix of luminophores and frequently encountered in phosphate bioceramics. However, the crystal structure of natural stanfieldite has never [...] Read more.
Stanfieldite, natural Ca-Mg-phosphate, is a typical constituent of phosphate-phosphide assemblages in pallasite and mesosiderite meteorites. The synthetic analogue of stanfieldite is used as a crystal matrix of luminophores and frequently encountered in phosphate bioceramics. However, the crystal structure of natural stanfieldite has never been reported in detail, and the data available so far relate to its synthetic counterpart. We herein provide the results of a study of stanfieldite from the Brahin meteorite (main group pallasite). The empirical formula of the mineral is Ca8.04Mg9.25Fe0.72Mn0.07P11.97O48. Its crystal structure has been solved and refined to R1 = 0.034. Stanfieldite from Brahin is monoclinic, C2/c, a 22.7973(4), b 9.9833(2), c 17.0522(3) Å, β 99.954(2)°, V 3822.5(1)Å3. The general formula of the mineral can be expressed as Ca7M2Mg7(PO4)12 (Z = 4), where the M = Ca, Mg, Fe2+. Stanfieldite from Brahin and a majority of other meteorites correspond to a composition with an intermediate Ca≈Mg occupancy of the M5A site, leading to the overall formula ~Ca7(CaMg)Mg9(PO4)12 ≡ Ca4Mg5(PO4)6. The mineral from the Lunar sample “rusty rock” 66095 approaches the M = Mg end member, Ca7Mg2Mg9(PO4)12. In lieu of any supporting analytical data, there is no evidence that the phosphor base with the formula Ca3Mg3(PO4)4 does exist. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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12 pages, 3235 KiB  
Article
Characterization of Biominerals in Cacteae Species by FTIR
by Alejandro De la Rosa-Tilapa, Agustín Maceda and Teresa Terrazas
Crystals 2020, 10(6), 432; https://doi.org/10.3390/cryst10060432 - 29 May 2020
Cited by 9 | Viewed by 3845
Abstract
A biomineral is a crystalline or amorphous mineral product of the biochemical activity of an organism and the local accumulation of elements available in the environment. The cactus family has been characterized by accumulating calcium oxalates, although other biominerals have been detected. Five [...] Read more.
A biomineral is a crystalline or amorphous mineral product of the biochemical activity of an organism and the local accumulation of elements available in the environment. The cactus family has been characterized by accumulating calcium oxalates, although other biominerals have been detected. Five species of Cacteae were studied to find biominerals. For this, anatomical sections and Fourier transform infrared, field emission scanning electron microscopy and energy dispersive x-ray spectrometry analyses were used. In the studied regions of the five species, they presented prismatic or spherulite dihydrate calcium oxalate crystals, as the predominant biomineral. Anatomical sections of Astrophytum asterias showed prismatic crystals and Echinocactus texensis amorphous silica bodies in the hypodermis. New findings were for Ariocarpus retusus subsp. trigonus peaks assigned to calcium carbonate and for Mammillaria sphaerica peaks belonging to silicates. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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14 pages, 3652 KiB  
Article
Krasnoshteinite, Al8[B2O4(OH)2](OH)16Cl4⋅7H2O, a New Microporous Mineral with a Novel Type of Borate Polyanion
by Igor V. Pekov, Natalia V. Zubkova, Ilya I. Chaikovskiy, Elena P. Chirkova, Dmitry I. Belakovskiy, Vasiliy O. Yapaskurt, Yana V. Bychkova, Inna Lykova, Sergey N. Britvin and Dmitry Yu. Pushcharovsky
Crystals 2020, 10(4), 301; https://doi.org/10.3390/cryst10040301 - 15 Apr 2020
Cited by 5 | Viewed by 2835
Abstract
A new mineral, krasnoshteinite (Al8[B2O4(OH)2](OH)16Cl4⋅7H2O), was found in the Verkhnekamskoe potassium salt deposit, Perm Krai, Western Urals, Russia. It occurs as transparent colourless tabular to lamellar crystals embedded up [...] Read more.
A new mineral, krasnoshteinite (Al8[B2O4(OH)2](OH)16Cl4⋅7H2O), was found in the Verkhnekamskoe potassium salt deposit, Perm Krai, Western Urals, Russia. It occurs as transparent colourless tabular to lamellar crystals embedded up to 0.06 x 0.25 x 0.3 mm in halite-carnallite rock and is associated with dritsite, dolomite, magnesite, quartz, baryte, kaolinite, potassic feldspar, congolite, members of the goyazite–woodhouseite series, fluorite, hematite, and anatase. Dmeas = 2.11 (1) and Dcalc = 2.115 g/cm3. Krasnoshteinite is optically biaxial (+), α = 1.563 (2), β = 1.565 (2), γ = 1.574 (2), and 2Vmeas = 50 (10)°. The chemical composition (wt.%; by combination of electron microprobe and ICP-MS; H2O calculated from structure data) is: B2O3 8.15, Al2O3 46.27, SiO2 0.06, Cl 15.48, H2Ocalc. 33.74, –O=Cl –3.50, totalling 100.20. The empirical formula calculated based on O + Cl = 33 apfu is (Al7.87Si0.01)Σ7.88[B2.03O4(OH)2][(OH)15.74(H2O)0.26]Σ16[(Cl3.79(OH)0.21]Σ4⋅7H2O. The mineral is monoclinic, P21, a = 8.73980 (19), b = 14.4129 (3), c = 11.3060 (3) Å, β = 106.665 (2)°, V = 1364.35 (5) Å3, and Z = 2. The crystal structure of krasnoshteinite (solved using single-crystal data, R1 = 0.0557) is unique. It is based upon corrugated layers of Al-centered octahedra connected via common vertices. BO3 triangles and BO2(OH)2 tetrahedra share a common vertex, forming insular [B2O4(OH)2]4− groups (this is a novel borate polyanion) which are connected with Al-centered octahedra via common vertices to form the aluminoborate pseudo-framework. The structure is microporous, zeolite-like, with a three-dimensional system of wide channels containing Cl- anions and weakly bonded H2O molecules. The mineral is named in honour of the Russian mining engineer and scientist Arkadiy Evgenievich Krasnoshtein (1937–2009). The differences in crystal chemistry and properties between high-temperature and low-temperature natural Al borates are discussed. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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13 pages, 2322 KiB  
Article
Crystallographic Insights into Uranyl Sulfate Minerals Formation: Synthesis and Crystal Structures of Three Novel Cesium Uranyl Sulfates
by Olga S. Tyumentseva, Ilya V. Kornyakov, Sergey N. Britvin, Andrey A. Zolotarev and Vladislav V. Gurzhiy
Crystals 2019, 9(12), 660; https://doi.org/10.3390/cryst9120660 - 9 Dec 2019
Cited by 13 | Viewed by 3731
Abstract
An alteration of the uranyl oxide hydroxy-hydrate mineral schoepite [(UO2)8O2(OH)12](H2O)12 at mild hydrothermal conditions was studied. As the result, four different crystalline phases Cs[(UO2)(SO4)(OH)](H2O)0.25 ( [...] Read more.
An alteration of the uranyl oxide hydroxy-hydrate mineral schoepite [(UO2)8O2(OH)12](H2O)12 at mild hydrothermal conditions was studied. As the result, four different crystalline phases Cs[(UO2)(SO4)(OH)](H2O)0.25 (1), Cs3[(UO2)4(SO4)2O3(OH)](H2O)3 (2), Cs6[(UO2)2(SO4)5](H2O)3 (3), and Cs2[(UO2)(SO4)2] (4) were obtained, including three novel compounds. The obtained Cs uranyl sulfate compounds 1, 3, and 4 were analyzed using single-crystal XRD, EDX, as well as topological analysis and information-based structural complexity measures. The crystal structure of 3 was based on the 1D complex, the topology of which was unprecedented for the structural chemistry of inorganic oxysalts. Crystal chemical analysis performed herein suggested that the majority of the uranyl sulfates minerals were grown from heated solutions, and the temperature range could be assumed from the manner of interpolyhedral linkage. The presence of edge-sharing uranyl bipyramids most likely pointed to the temperatures of higher than 100 °C. The linkage of sulfate tetrahedra with uranyl polyhedra through the common edges involved elevated temperatures but of lower values (~70–100 °C). Complexity parameters of the synthetic compounds were generally lower than that of uranyl sulfate minerals, whose structures were based on the complexes with the same or genetically similar topologies. The topological complexity of the uranyl sulfate structural units contributed the major portion to the overall complexity of the synthesized compounds, while the complexity of the respective minerals was largely governed by the interstitial structure and H-bonding system. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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12 pages, 2042 KiB  
Article
Synthesis and Characterization of (Ca,Sr)[C2O4]∙nH2O Solid Solutions: Variations of Phase Composition, Crystal Morphologies and in Ionic Substitutions
by Aleksei V. Rusakov, Mariya A. Kuzmina, Alina R. Izatulina and Olga V. Frank-Kamenetskaya
Crystals 2019, 9(12), 654; https://doi.org/10.3390/cryst9120654 - 8 Dec 2019
Cited by 6 | Viewed by 3414
Abstract
To study strontium (Sr) incorporation into calcium oxalates (weddellite and whewellite), calcium-strontium oxalate solid solutions (Ca,Sr)[C2O4]∙nH2O (n = 1, 2) are synthesized and studied by a complex of methods: powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) [...] Read more.
To study strontium (Sr) incorporation into calcium oxalates (weddellite and whewellite), calcium-strontium oxalate solid solutions (Ca,Sr)[C2O4]∙nH2O (n = 1, 2) are synthesized and studied by a complex of methods: powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. Two series of solid solutions, isomorphous (Ca,Sr)[C2O4]·(2.5 − x)H2O) (space group I4/m) and isodimorphous Ca[C2O4]·H2O(sp.gr. P21/c)–Sr[C2O4]·H2O(sp.gr. P 1 - ), are experimentally detected. The morphogenetic regularities of their crystallization are revealed. The factors controlling this process are discussed. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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18 pages, 3796 KiB  
Article
Crystal Structures and High-Temperature Vibrational Spectra for Synthetic Boron and Aluminum Doped Hydrous Coesite
by Yunfan Miao, Youwei Pang, Yu Ye, Joseph R. Smyth, Junfeng Zhang, Dan Liu, Xiang Wang and Xi Zhu
Crystals 2019, 9(12), 642; https://doi.org/10.3390/cryst9120642 - 5 Dec 2019
Cited by 7 | Viewed by 2982
Abstract
Coesite, a high-pressure SiO2 polymorph, has drawn extensive interest from the mineralogical community for a long time. In this study, we synthesized hydrous coesite samples with different B and Al concentrations at 5 and 7.5 GPa (1273 K). The B concentration could [...] Read more.
Coesite, a high-pressure SiO2 polymorph, has drawn extensive interest from the mineralogical community for a long time. In this study, we synthesized hydrous coesite samples with different B and Al concentrations at 5 and 7.5 GPa (1273 K). The B concentration could be more than 400 B/106Si with about 300 ppmw H2O, while the Al content can be as much as 1200 to 1300 Al/106Si with CH2O restrained to be less than 10 ppmw. Hence, B-substitution may prefer the mechanism of Si4+ = B3+ + H+, whereas Al-substitution could be dominated by 2Si4+ = 2Al3+ + OV. The doped B3+ and Al3+ cations may be concentrated in the Si1 and Si2 tetrahedra, respectively, and make noticeable changes in the Si–O4 and Si–O5 bond lengths. In-situ high-temperature Raman and Fourier Transformation Infrared (FTIR) spectra were collected at ambient pressure. The single crystals of coesite were observed to be stable up to 1500 K. The isobaric Grüneisen parameters (γiP) of the external modes (<350 cm−1) are systematically smaller in the Al-doped samples, as compared with those for the Al-free ones, while most of the OH-stretching bands shift to higher frequencies in the high temperature range up to ~1100 K Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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11 pages, 13644 KiB  
Article
Bacterial Effect on the Crystallization of Mineral Phases in a Solution Simulating Human Urine
by Alina R. Izatulina, Anton M. Nikolaev, Mariya A. Kuz’mina, Olga V. Frank-Kamenetskaya and Vladimir V. Malyshev
Crystals 2019, 9(5), 259; https://doi.org/10.3390/cryst9050259 - 18 May 2019
Cited by 10 | Viewed by 5320
Abstract
The effect of bacteria that present in the human urine (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus) was studied under the conditions of biomimetic synthesis. It was shown that the addition of bacteria significantly affects both the phase composition [...] Read more.
The effect of bacteria that present in the human urine (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus) was studied under the conditions of biomimetic synthesis. It was shown that the addition of bacteria significantly affects both the phase composition of the synthesized material and the position of crystallization boundaries of the resulting phosphate phases, which can shift toward more acidic (struvite, apatite) or toward more alkaline (brushite) conditions. Under conditions of oxalate mineralization, bacteria accelerate the nucleation of calcium oxalates by almost two times and also increase the amount of oxalate precipitates along with phosphates and stabilize the calcium oxalate dihydrate (weddellite). The multidirectional changes in the pH values of the solutions, which are the result of the interaction of all system components and the crystallization process, were analyzed. The obtained results are the scientific basis for understanding the mechanisms of bacterial involvement in stone formation within the human body and the creation of biotechnological methods that inhibit this process. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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18 pages, 3431 KiB  
Article
The High Pressure Behavior of Galenobismutite, PbBi2S4: A Synchrotron Single Crystal X-ray Diffraction Study
by Paola Comodi, Azzurra Zucchini, Tonci Balić-Žunić, Michael Hanfland and Ines Collings
Crystals 2019, 9(4), 210; https://doi.org/10.3390/cryst9040210 - 18 Apr 2019
Cited by 4 | Viewed by 3127
Abstract
High-pressure single-crystal synchrotron X-ray diffraction data for galenobismutite, PbBi2S4 collected up to 20.9 GPa, were fitted by a third-order Birch-Murnaghan equation of state, as suggested by a FE-fE plot, yielding V0 = 697.4(8) Å3 [...] Read more.
High-pressure single-crystal synchrotron X-ray diffraction data for galenobismutite, PbBi2S4 collected up to 20.9 GPa, were fitted by a third-order Birch-Murnaghan equation of state, as suggested by a FE-fE plot, yielding V0 = 697.4(8) Å3, K0 = 51(1) GPa and K’ = 5.0(2). The axial moduli were M0a = 115(7) GPa and Ma’ = 28(2) for the a axis, M0b = 162(3) GPa and Mb’ = 8(3) for the b axis, M0c = 142(8) GPa and Mc’ = 26(2) for the c axis, with refined values of a0, b0, c0 equal to 11.791(7) Å, 14.540(6) Å 4.076(3) Å, respectively, and a ratio equal to M0a:M0b:M0c = 1.55:1:1.79. The main structural changes on compression were the M2 and M3 (occupied by Bi, Pb) movements toward the centers of their respective trigonal prism bodies and M3 changes towards CN8. The M1 site, occupied solely by Bi, regularizes the octahedral form with CN6. The eccentricities of all cation sites decreased with compression testifying for a decrease in stereochemical expression of lone electron pairs. Galenobismutite is isostructural with calcium ferrite CaFe2O4, the suggested high pressure structure can host Na and Al in the lower mantle. The study indicates that pressure enables the incorporation of other elements in this structure, increasing its potential significance for mantle mineralogy. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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Review

Jump to: Editorial, Research

28 pages, 4624 KiB  
Review
Crystal Chemistry and Structural Complexity of Natural and Synthetic Uranyl Selenites
by Vladislav V. Gurzhiy, Ivan V. Kuporev, Vadim M. Kovrugin, Mikhail N. Murashko, Anatoly V. Kasatkin and Jakub Plášil
Crystals 2019, 9(12), 639; https://doi.org/10.3390/cryst9120639 - 30 Nov 2019
Cited by 19 | Viewed by 4475
Abstract
Comparison of the natural and synthetic phases allows an overview to be made and even an understanding of the crystal growth processes and mechanisms of the particular crystal structure formation. Thus, in this work, we review the crystal chemistry of the family of [...] Read more.
Comparison of the natural and synthetic phases allows an overview to be made and even an understanding of the crystal growth processes and mechanisms of the particular crystal structure formation. Thus, in this work, we review the crystal chemistry of the family of uranyl selenite compounds, paying special attention to the pathways of synthesis and topological analysis of the known crystal structures. Comparison of the isotypic natural and synthetic uranyl-bearing compounds suggests that uranyl selenite mineral formation requires heating, which most likely can be attributed to the radioactive decay. Structural complexity studies revealed that the majority of synthetic compounds have the topological symmetry of uranyl selenite building blocks equal to the structural symmetry, which means that the highest symmetry of uranyl complexes is preserved regardless of the interstitial filling of the structures. Whereas the real symmetry of U-Se complexes in the structures of minerals is lower than their topological symmetry, which means that interstitial cations and H2O molecules significantly affect the structural architecture of natural compounds. At the same time, structural complexity parameters for the whole structure are usually higher for the minerals than those for the synthetic compounds of a similar or close organization, which probably indicates the preferred existence of such natural-born architectures. In addition, the reexamination of the crystal structures of two uranyl selenite minerals guilleminite and demesmaekerite is reported. As a result of the single crystal X-ray diffraction analysis of demesmaekerite, Pb2Cu5[(UO2)2(SeO3)6(OH)6](H2O)2, the H atoms positions belonging to the interstitial H2O molecules were assigned. The refinement of the guilleminite crystal structure allowed the determination of an additional site arranged within the void of the interlayer space and occupied by an H2O molecule, which suggests the formula of guilleminite to be written as Ba[(UO2)3(SeO3)2O2](H2O)4 instead of Ba[(UO2)3(SeO3)2O2](H2O)3. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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16 pages, 2056 KiB  
Review
Synthesis Methods and Favorable Conditions for Spherical Vaterite Precipitation: A Review
by Donata Konopacka-Łyskawa
Crystals 2019, 9(4), 223; https://doi.org/10.3390/cryst9040223 - 25 Apr 2019
Cited by 107 | Viewed by 9152
Abstract
Vaterite is the least thermodynamically stable anhydrous calcium carbonate polymorph. Its existence is very rare in nature, e.g., in some rock formations or as a component of biominerals produced by some fishes, crustaceans, or birds. Synthetic vaterite particles are proposed as carriers of [...] Read more.
Vaterite is the least thermodynamically stable anhydrous calcium carbonate polymorph. Its existence is very rare in nature, e.g., in some rock formations or as a component of biominerals produced by some fishes, crustaceans, or birds. Synthetic vaterite particles are proposed as carriers of active substances in medicines, additives in cosmetic preparations as well as adsorbents. Also, their utilization as a pump for microfluidic flow is also tested. In particular, vaterite particles produced as polycrystalline spheres have large potential for application. Various methods are proposed to precipitate vaterite particles, including the conventional solution-solution synthesis, gas-liquid method as well as special routes. Precipitation conditions should be carefully selected to obtain a high concentration of vaterite in all these methods. In this review, classical and new methods used for vaterite precipitation are presented. Furthermore, the key parameters affecting the formation of spherical vaterite are discussed. Full article
(This article belongs to the Special Issue Mineralogical Crystallography)
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