Decorative Stone Research Articles

Petrological Characteristics and Physico-Mechanical Properties of Dokhan Volcanics for Decorative Stones and Building Material Applications

Wide varieties of igneous rocks are extensively utilized as stones for decoration purposes and as a potential source for building. With the use of petrological (mineralogical and chemical) and physico-mechanical analyses, the current work accurately mapped the Dokhan Volcanics (DV) and utilized them as decorative stones and their prospective in building materials using Frattini’s test. Field observations indicate that metavolcanics, DV, and monzogranites are the principal rock units exposed in the studied area. The DV rocks are characterized by a dense series of stratified, rhyolitic to andesitic lava interspersed with a few pyroclastics. Andesite, andesite porphyry, dacite, and rhyolite are the primary representatives of the selected DV. The lack of infrequent appearance of mafic units in the current volcanic eruptions indicates that the primary magma is not mantle-derived. This is supported by their Mg# (17.86–33.57). Additionally, the examined DV rocks have Y/Nb ratios above 1.2, suggesting a crustal source. The role of fractionation is interpreted by their variation from andesite passing through dacite to rhyolite, which is indicated by gradual negative distribution groups between silica and TiO2, Fe2O3, CaO, MgO, Co, and Cu from andesite to rhyolitic lava. Additionally, a wide range of widely used DV rocks like Y/Nb, Rb/Zr, and Ba/Nb point to crustal contamination in the rhyolitic rocks. The partial melting of the lower crust can produce andesitic magma, which ascend to higher crustal levels and form lava of calc-alkaline. A portion of this lava may split, settle at shallow crustal depths, and undergo differentiation to create the DV rocks. Based on the results of physico-mechanical properties, the studied samples met the requirements for natural stone to be used as decorative stones, whether as interior or exterior installations. The pozzolanic assessment of the studied rocks revealed their usability as supplementary cementitious materials in the building sector.

Data Collection for Cultural Heritage Risk Management: the Damage Map through Heritage Building Information Modeling (HBIM) Project Applied to the Façade of St Francis of Assisi, Ouro Preto, Brazil

ABSTRACT The development of precise analytical methodologies, together with the systematic use of verifiable data, aims to raise standards for treatment, risk management, and maintenance programs. This endeavor aims to diminish the frequency of subsequent restoration cycles, thereby positively impacting public spending and fostering the preservation of the authentic characteristics of historical buildings, particularly by mitigating the effects of decay. The Damage Map through Heritage Building Information Modeling (HBIM) project, funded by the National Council for Scientific and Technological Development (CNPq) and Minas Gerais Research Support Foundation (FAPEMIG), both Brazil, aims to establish protocols for risk management in historical buildings, with a focus on decorative stone elements integrated into the construction. For this reason, the stone relief on the façade of the church of St Francis of Assisi in Ouro Preto, Brazil, was chosen as a case study. This paper outlines the data collection methodology applied to study the stone. This approach encompasses historical examinations of restoration cycles, along with preliminary findings derived from extensive fieldwork, conducted by a multidisciplinary team in 2023. It elucidates the data collection stage, employing photography and aerial photogrammetry, ultraviolet fluorescence photography, mobile laser scanning, and thermography. Subsequently, all collected data will be used to construct a diagnostic model within the HBIM.

Radiometric and petrographic characterization of El-Yatima granite: Evaluating radiological risks and mineralogical features

The current investigation aims to assess the potential of El-Yatima granitic pluton as a decorative stone by examining its natural radioactivity and mineralogical elements. Specifically, the study aims to determine the concentrations of radionuclides 40K, 232Th, and 226Ra, perform petrographic analyses, and evaluate the associated radiological risks to determine the safety and usability of the granite in construction and decoration, as well as to assess the potential of these granitic rocks as a safe and effective decorative stone for various applications. It has a 12 km2 surface area of 812 m above sea level. It is situated in the Eastern Central Desert. Its hypidiomorphic texture, medium-to-coarse grain size, and predominant composition of K-feldspars, quartz, and plagioclase are observed, along with minute amounts of muscovite and biotite. By employing NaI (Tl) gamma-ray spectroscopy, the natural radionuclide concentrations of 40K, 232Th, and 226Ra in El-Yatima granitic rocks were ascertained. Additionally, radiological concerns were identified for the materials that were examined. The average concentrations of radionuclides 40K, 232Th, and 226Ra are 178 Bqkg−1, 44 Bqkg−1, and 41 Bqkg−1, respectively. The following are the computed values: 117 Bqkg−1, 0.43, 0.32, 53 nGyh−1, average radium equivalent (Raeq), hazard indices (Hin and Hex) and dose rate (D), respectively. When compared to levels typically indicated, it was discovered that its values were within the worldwide standard. The study's findings could be a starting point for radiometric data for upcoming surveillance and epidemiological research.

RECYCLING OF MATERIALS FROM THE EXCAVATION OF THE "POČITELJ" TUNNEL AND INCORPORATION OF THE OBTAINED PRODUCTS IN THE TUNNEL THROUGH CONCRETE AND BLINDING LAYER

In civil engineering or road construction, especially when constructing tunnels, large quantities of excavated material are created. In many cases, this material, if properly treated and processed, can be recycled and reused on site. If this material is not treated as planned from the beginning of the project, but is taken to the landfill and mixed with bad material or construction waste, then when the need for it arises, it is difficult to separate it and return it to the construction process. In the simplest case, the material can be used as an embankment to the extent that it meets the requirements regarding the quality of the embankment material. Better quality material can often be recycled to make fractions for various types of concrete, buffer aggregates or decorative stone walls (architectural stone). In the current example of the "Počitelj" tunnel, through tests of fractions, definition of recipes, recycled material from tunnel excavation was successfully used as aggregate for shotcrete, concrete for inner lining and construction, buffer, bedding for laying pipes and making front slopes from crushed stone. This reduced the purchase and transport of aggregates from local quarries to the minimum possible, thus saving resources, with financial benefit. In summary, through this example, it can be noted that the reuse of tunnel excavation will play an important role for future tunnel projects due to environmental and economic reasons. Keywords: tunnel, excavation, limestone, concrete, blinding layer, recycling

Preserving Authentic Decoration in the Entrance Spaces of Residential Buildings in Eastern Galicia from the late 19th to the First Third of the 20th Century: Restoration Experience

The special role in shaping the entrance spaces of buildings, their artistic expressiveness belonged to decorative art, as architects used such materials as artistic wood, artistic metal, artistic glass, artistic ceramics, artistic paintings, sculptural forms, decorative stone and other elements for decorating entrance spaces. Sometimes, one motif could be the main focus in the decor of entrance spaces, echoing with artistic paintings, decor on ceramic tiles, etched pseudo-stained glass, supraports and wrought ironwork of stair railings according to the principle of interaction of arts. However, there are cases of staircases, artistic paintings or stained-glass windows that are not continued in the patterns of ceramic tiles, decor of walls and ceilings, railing enclosures, or artistic solutions of entrance gates. In such cases, these decorative elements act as an accent in the interior. Natural studies allow to systematize the typology of doors based on a number of characteristics: material of manufacture, stylistic execution, principles of decorative solution, location of artistic decoration, type of ornament of wrought iron grilles and so on. However, alongside negative examples of the state of entrance spaces, there is also positive experience of their preservation and restoration.

Decorative stone techniques of Italian masters

Italian mastery of decorative stones can be traced through a variety of techniques, from the period of the Roman Empire through to the nineteenth century at least. Roman mosaic work was found across the Roman Empire, and the remains of mosaics are widely admired. In Roman Britain, artisans adapted their classic stone palette through the use of local stones, delivering greys, green and browns. Post‐Roman artistry is seen through the reuse of broken stones known by Cosmati mosaicists; the Cosmati pavement in Westminster Abbey, London is one of the best known of its type. Hardstone work—Pietre Dure—employing many stones in intricate detail, was brought back from Italy by all those on the Grand Tour in eighteenth century Europe are to be found in many grand houses. Finally, the incredible ledger stones of the Knights of St John in Malta are yet another example of the high art and craft of the Italian masters of decorative stone.

Economic feasibility of Gabal Um Takha leucogranitic intrusion, South Sinai, Egypt: Integrated remote sensing, geochemical, aeromagnetic, and geotechnical approach

Variable granitic rocks are widely used as decorative stones. The present work conducted accurate mapping and the utilization of a large leucogranitic intrusion (Um Takha area) as a decorative stones through physico-mechanical tests, mineralogical and geochemical compositions. These leucogranites are medium-grained, classified as syenogranites, peraluminous, calc-alkaline, and highly evolved granites developed during the post-collisional setting. This study utilized various remote sensing techniques to identify the Um Takha leucogranitic using ASTER and Landsat-9 data. A novel FCC band ratio of the ASTER image (RGB: b1+b3/b2, b2/b1, b7+b9/b8) was created, along with the Landsat-9 FCC band ratio of (4/7, 3/4, and 2/1) in the RGB, to effectively map the distribution of in the study area. These results, combined with field observation, led to the creation of a new modified geological map of the Um Takha area. The analysis of magnetic data reveals that the depth of magnetic sources under the study area ranges between 170 m and 2215 m, as calculated by source parameter image and Euler deconvolution techniques. The application of horizontal gradient, tilt derivatives and improved logistic techniques reveals that the major structural trend affecting the study area is in the N–S, NNE-SSW and NNW-SSE direction. The physico-mechanical properties of leucogranitic rocks (M13) fulfilled the requirements of dimension stone in terms of bulk density, compressive strength, and to some extent water absorption. Therefore, they could be acceptable for interior use and the light-duty purposes of exterior use, such as facades and cladding. This suggest that a large resources of leucogranitic can be used as a decorative stones.

MUSEUM OF PRECIOUS AND DECORATIVE STONES – HISTORY, RECOGNITION, DEVELOPMENT

The Museum of Precious and Decorative Stones is one of the well-known museums dedicated to geological topics. The creation of the Museum developed in parallel with the research and exploitation of the Volyn chamber pegmatite deposit. The collection of specimens from the Volyn chamber pegmatite deposit, minerals of the natural resource base of Ukraine and minerals and rocks from deposits around the world has deservedly received the status of unique. This collection, which is the result of many years of hard work by local specialists, is known and respected both among geological experts and numerous nature lovers. Many of the Museum's exhibits are unique and have no analogues in the world. The collection is of exceptional importance for science and cannot be reproduced in the event of its destruction, as the loss of rare exhibits cannot be replaced by other similar ones. Eight specimens from the collection have their own names, dedicated both to prominent scientists of world renown and to names that reflect the characteristic features that appear in the world mineralogical literature. The Museum's development strategy envisages: dissemination of geological knowledge, attraction of a wide range of visitors, ensuring full functioning as a scientific, cultural and educational institution, further development as a centre of geological and mineralogical life, raising the level of its work in accordance with modern requirements, infrastructure development, and expansion of online resources.

Test the Effectiveness of Eco-Enzyme Bioremediation as a Reducing Agent for Natural Stone Waste on Rice Plant Productivity and Water Quality in Dukupuntang District

Water is a natural resource that is needed for all living things. Likewise with the river used for irrigation of agricultural land. The Cigayem River is located in Dukupuntang District, Cirebon Regency. Above the river there are many natural stone cottage industries. The processing of natural stone into decorative stone requires a lot of water for its processing, so that a lot of river water in this area is polluted from this home industry activity. The waste is in the form of powder cut from natural stone with water which is directly channeled into irrigation canals without being processed first. The effect is siltation of irrigation canals and decreased water quality. This decrease in water quality has an impact on rice productivity in heavily affected areas. Pollution that occurs in irrigation canals in the study area can be identified by physical changes such as color and other impacts such as decreased productivity of rice yields in the study area since the establishment of the natural stone industry. The decline in rice productivity will threaten the sustainability of rice farming in central areas. Wastewater treatment technology has been developed a lot, but not all home industries can carry out waste treatment at a high cost. Eco enzyme can be a solution to waste pollution that pollutes rivers at a relatively low cost, easy to obtain and sustainable because all materials do not contain harmful chemicals and residues.

Initial research results on the possibility of using metacarbonate formations in Tan Lap - Cho Don - Bac Kan province as decorative stone

Based on the study of the characteristics of materials, structure, textures and physical properties of metacarbonate rocks at Tan Lap area, Cho Don district, Bac Kan province, it is possible to provide the initial possibility of using these rocks as decoration stones. Methods applied in the study include field investigations and sampling; sample analysis for thin-section microscopes, for the chemistry of sicilate and physical properties. The results indicate that metacarbonate rocks consist mainly of marbles which are allocated within the 3rd unit of the upper part of Mia Le formation (D1ml2). The rocks are thick layered structure, granoblastic texture, fine- to medium-grained marbles. Cao is the predominate chemical composition while heavy metals and radioactive elements are of very low contents. The rocks are pure white, exhibiting high color fastness and gloss. The outcomes of this study could serve as a scientific basis for guiding in exploration, exploitation, and utilization of mineral resources (marble) in the Tan Lap area particularly as well as in Vietnam's territory.

Threat of non-metallic mining on the integrity of the Tocuyo River basin, Lara state, Venezuela

There are various conflicts of usage in the Tokuyo River Basin of Lala Prefecture. The contradiction is that in a semi-arid and water scarce area, the soil has many natural resources, among which the most prominent are non-metallic minerals ((NMM), such as silica, the best clay and a series of decorative stones in the country. The public policies of the State and local governments prevail in this territory. They encourage NMM mining, therefore, criticism of an extractivist economy that has historically dominated the country arises. Through an exhaustive documentary review, results show that there are few references to environmental impact studies associated with NMM mining. There is evidence of open-pit mining near rivers and streams, which exposes areas to erosion and sediment production due to the typical erratic rains that affect the Tocuyo, Morere, Diquiva and Curarigua rivers. The promotion of mining activities by economic interests without the independent participation of environmental institutions puts the integrity of the basin at risk. The situation requires the activism of social movements to denounce the impacts that put, among other things, the future availability of water for human consumption and food production at risk.

Research on Green Consumption Based on Visual Evaluation Method—Evidence from Stone Flooring Industry

Blind consumption discovered in the real application of flooring does not produce the visually anticipated impression, leading to additional time costs and stone flooring waste. Consumers cannot clearly articulate their visual imaging needs when purchasing stone flooring. Due to consumers’ lack of understanding of the visual imagery style of decorative stone flooring, manufacturers are unable to produce more visual styles of stone flooring in response to consumer demand, which leads to an unorganized production process and the wasting of stone resources. Additionally, manufacturers are unable to receive feedback on market demand, which makes communication links between sales teams difficult. A total of 40 adjectives were considered the most appropriate in a pool of 110 adjectives for the visual imagery evaluation of stone after ten interior design professionals with experience in decorative stone applications had narrowed the selection. Following this, a general consumer semantic difference method questionnaire survey and questionnaire data factor analysis statistics were used to create 10 sets of visual imagery adjectives for marble flooring, which were then divided into 10 different types of marble flooring. Following the computer simulation drawing with the 10 groups of visual imagery adjectives design questionnaire, the consumers completed the visual imagery evaluation questionnaire survey. They received a 304-question valid questionnaire, and using the triangular fuzzy number operation in fuzzy theory, they arrived at 10 marble floors in the visual imagery evaluation score. In order to clarify the current consumer demand for stone floor imagery, the high sales volume of stone flooring on the market for visual style division, which can guide consumers according to their visual needs for an efficient choice, can enhance the efficiency of communication between consumers and sellers. It can also help enterprises clarify the market consumer demand for orderly production to achieve the purpose of green consumption and to ensure the sustainable development of the decorative stone flooring market.

Епіграфіка та декоративне кам’яне різьблення на пам’ятках Аккермана XV–XVIII ст.

Епіграфіка та декоративне кам’яне різьблення на пам’ятках Аккермана XV–XVIII ст.

Mineralogical constituents and radioactivity analysis of commercial granitic ornamental stones: Assessing suitability and radiation safety

Several commercial granitic rocks are widely used as decorative material (ornamental stones) due to their durability and fantastic colors. The present study aims to identify the mineralogical constituents as well as natural radioactivity of seven granitic rocks known as Gandonna, Pink Granite, Fantazia, Buff granites I, Buff granites II, Qusseir brown, red granites in order to deduce their suitability for different applications (decorative stone). Accordingly, in the petrographic investigation, the examined rocks comprise different proportions of essential minerals (potash feldspar, quartz, and albite) with some secondary minerals such as kaolinite and chlorite minerals.238U,226Ra,232Th and40K activity concentrations were detected by using NaI (Tl) scintillation γ-ray technique. Fantasia (av. 4.13 ± 5.85, 10.77 ± 1.9 Bqkg−1), and Gandonna (av. 12.4 ± 10.12, 35.01 ± 3.81 Bqkg−1) samples have the lowest mean238U, and232Th activities value, relative to other rock samples, which are lower than the recommended levels of UNSCEAR. Except for absorbed dose rate, numerous radiological indices such as outdoor and indoor annual effective dose, radium equivalent activity, external and internal indices, excess lifetime cancer risk and organs of effective dose are calculated for the examined stations to deduce the radiation effects on human organs. The obtained results reveal that the natural gamma radiation from these rocks is within acceptable limits.

Radioactivity in decorative building materials: Insights from Johor, Malaysia

The appearance and atmosphere of a building can be enhanced by the aesthetic appeal of its decoration. Building materials used for construction purposes, such as rocks, stones, and dyes, are typically of natural origin and may contain naturally occurring radioactive materials (NORM) within their elements. Hence, evaluating the potential risk of radiation exposure to occupants is crucial to ensure that it falls within acceptable levels. In this regard, a study was conducted in Johor, Malaysia using gamma spectroscopy to measure the natural radioactivity of 18 indoor decorative stones, including granite, porcelain, marble, and quartz. The observed radioactivity concentration ranged from 0.23 to 317.25 Bq kg−1, 1.35–116.81 Bq kg−1 and 0.74–2712.55 Bq kg−1 for 238U, 232Th and 4 K, respectively. Various radiological quantities were calculated and compared with recommended values established by the international commission bodies and findings from previous research conducted in other countries. Furthermore, the study employed Virtual Monte Carlo software (VMC-DC) to estimate dose equivalents for all samples through simulation. The highest dose rate was observed in sample G6 at 0.0852 μSv h−1, and with an exposure time of 19 h per day, the annual effective dose was calculated to be 0.5906 mSv y−1, which is well below the maximum dose limit of 1 mSv y−1 as recommended by IAEA. It can be concluded that the indoor decorative stones examined in Johor, Malaysia are safe for use in buildings from a radiological perspective, as they do not pose any significant radiological hazards.

Indigenous connections with the resourcescape in the Russian North and Siberia

ABSTRACT This article analyzes the impacts of resource extraction on indigenous communities focusing on the case studies of two indigenous minorities in Russia: Veps in Karelia and Soiots in Buriatia. Veps and Soiots have a history of engagement with resource extraction, which goes back to the eighteenth century and continues till the present time. By focusing on two models of human – landscape relations and industrial development in indigenous territories, the article discusses the perceptions of decorative stones among Veps and Soiot households. It specifically focuses on parallels between mining and other forms of economic activities such as hunting, fishing, or tourism development. The article demonstrates that different forms of resource extractions are closely connected in Veps and Soiot villages, forming a common resourcescape. Both mining and other forms of extracting natural resources contribute to local visions of sustainability, which unite various forms of engagement with nature.

Leitha limestone from St. Margarethen (Austria) and Fertőrákos (Hungary) used in Slovakia as a natural stone

In Western Slovakia, especially in the Bratislava region and Trnava region, Leitha limestone of the Badenian (Langhian – early Serravalian) age from St. Margarethen in Austria was widely used for architectural articles and sculptures (200 realizations), alternatively a similar limestone from Fertőrákos in Hungary. 380 tombstones were identified only in Bratislava cemeteries. From the second half of the 17th century to the first half of the 20th century, the limestones were one of the most used in Slovakia due to their light dressing and relatively homogeneous appearance. The strongly porous coarse-grained to medium-grained the Leitha limestone has the appearance of sandstone and is composed of a predominance of red algae nodules over foraminifers, sea urchin, moss and shell fragments. The rhodoliths, pectenoids and oysters are scattered in the Leitha limestones up to a few cm size, which distinguish the limestone type from other the Leitha limestones and similar Sarmatian limestones. The limestone is dominated by rhodolithes in the St. Margarethen quarry and by bivalves and macroscopic quartz in Fertőrákos quarry. Porous limestones are exposed to weathering outdoors, leading to mass loss, flaking, sulphate efflorescence, black crusts from microscopic organisms and the colonization by lichens and mosses. The peak of limestone use for public buildings and sculptures was the years 1745 to 1780 (reign of Maria Theresa), and about 1880 to 1915, when there was relative prosperity and machine production began. The tombstones made of the Leitha limestones shifts to a peak between 1905 and 1925. In the 20th century, the Leitha limestones gave way to a competition from Czech decorative stones.

THE HISTORY OF THE CREATION OF THE MUSEUM OF PRECIOUS AND DECORATIVE STONES. HISTORICAL AND SCIENTIFIC ASPECTS OF THE SCIENTIFIC AND PRACTICAL CONFERENCE «MINERAL AND RAW MATERIAL WEALTH OF UKRAINE: WAYS OF OPTIMUM USE»

The article provides brief information about the history of the creation of the Museum of Precious and Decorative Stones and information about the initiation by the museum of the scientific and practical conference «Mineral and raw material wealth of Ukraine: ways of optimal use». In the historical aspect, the organizational and scientific aspects of the conferences that took place during 2008-2021 are covered.

A prediction method for abrasion loss rate of some Egyptian carbonate rocks due to cyclic salt crystallization weathering using physico-mechanical deterioration: insights from laboratory investigations

Salt crystallization is the most important weathering processes that causes problems for rocks used as building stones. Therefore, assessment of the physico-mechanical properties of stones against cyclic salt crystallization is a critical issue for rock engineering applications in salty environmental conditions especially prone to abrasion. This research aims at investigating the relationship between the degradation of various physico-mechanical properties including apparent porosity, point load index, unconfined compression strength and abrasion loss rate for rocks during salt weathering process. For showing rock weathering in the salt crystallization process, five kinds of carbonate rocks were sampled from different areas of Egypt and subject to cyclic salt crystallization, up to twenty cycles. The variation rates of their physico-mechanical characteristics and abrasion loss values were calculated after each five cycles of salt weathering. The results showed that the studied rocks are suitable for use as building and decorative stones in areas prone to crystallization of salts, but attention must be paid to rocks with high porosity and low strength characteristics such as El-Minia limestone specimens. It was also found that there are strong linear correlations between the physico-mechanical degradation parameters and the abrasion loss rate of the studied rock samples at the end of the twentieth cycle of salt weathering. These relationships may be used to estimate the abrasion loss rate of the studied rock types against the cyclic salt weathering conditions and hence to make a rapid evaluation of the stone durability.

Treatment of material surfaces with bacterial solutions to initiate the deposition of calcium carbonate. Review

Introduction. Surface treatment plays an important role in protecting decorative stone and concrete from the effects of harmful environmental factors. To protect stone surfaces, dietary supplements in the form of carbonatogenic bacteria, the product of which is calcium carbonate, can be used.Materials and methods. The selection and analysis of publications containing the results of research and experiments, which allow to draw conclusions about the feasibility of using bacterial solutions for surface treatment, has been carried out.Conclusions. The formation of a layer of calcium carbonate on the surface of the material reduces gas permeability, reduces water absorption, increasing the durability of concrete. It was found that the surface treatment of cement stone with solutions containing cultures of urobacteria strengthens the surface layer of the stone, but does not restore its strength. It is important that the formed layer of calcium carbonate on the surface of the material does not clog its pores. The chemical and structural similarity between the processed material and the resulting carbonate compounds must be observed. The dosage of urea and calcium chloride should correspond to the number of bacterial cells, since excess components of the nutrient medium leads to their accumulation in the pores.