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Engineered covers are commonly used to control the potential environmental problems related to acid mine drainage and contaminated seepage from tailings and waste rock storage facilities. Cyclical environmental weathering processes, such as freeze-thaw and wet-dry cycles, can cause rock degradation. However, these processes are usually not explicitly considered when selecting coarse-grained geomaterials for use as cover materials, even though they could be responsible for a decrease in cover performance over time. This study assesses the durability of a non-potentially acid-generating soapstone waste rock unit with respect to freeze-thaw and wet-dry cycles. This waste rock is intended for use as a cover material for the reclamation of mine tailings and waste rock storage facilities at a site in the Canadian Arctic. An experimental approach was developed based on existing standard and non-standard laboratory methods. Degradation tests were conducted on rock cores, rock slabs, and < 50-mm granular materials. These tests examined changes in selected physical and mechanical properties before and after 20 and 80 freeze-thaw and wet-dry cycles. The high density, low water absorption index, and low apparent porosity of the fresh waste rocks suggested excellent rock durability, which was confirmed by the degradation tests that showed acceptable mass losses and negligible evolution of the material's physical and mechanical properties over time. Considering the results of this study, the studied waste rock unit was identified as an excellent construction material for mine closure purposes. The experimental approach developed for this study could be included in cover design methodologies and applied widely in the selection of rocks for use in mine reclamation schemes in cold regions. [ABSTRACT FROM AUTHOR]

Background: The hand-carved, traditional, versatile kitchen utensils made up of soft soapstone are used and treasured since the rise of civilization in India, especially in the southern states: Andhra Pradesh, Telangana, Tamil Nadu, Karnataka, and Kerala. They are called as rathi chippa and kal chatti and employed for cooking, serving, and storing food for many generations. Results: The soft soapstone is chemically characterized as steatite and mainly composed of talc. The cookware of varying colors, shapes, and sizes are hand made by the artisans from Tamil Nadu state and offered for sale in the shops located in temple premises and during annual temple festivals. The delicate cookware requires proper conditioning and care while cooking, handling, and cleaning. Such inert cookware has positive quality properties such as low dielectric, high temperature resistance, high density and high mechanical strength. These characteristics have been reflected on the cookware application in cooking foods that require longer cooking time over a gentle fire, and sour, acidic, tamarind containing dishes. They are extensively used for making liquid, gravy-based curries and semi-solid foods; storing and preserving milk, curd, buttermilk, rock salt, tamarind, extracts, pickles, etc. Conclusions: Notably, the food cooked in soapstone cookware retains the natural, authentic, original aroma and taste. As an insulator, it acts as a casserole by keeping the food hot for longer durations. Being extremely dense and non-porous, it is impervious to bacterial penetration and prevents the bacterial growth on the surface as well as extends the shelf life of cooked foods. Fascinated by traditional importance, distinct taste and health benefits, and tired of factory-made things, the current generations are shifting toward these handmade, exclusive soapstone products. [ABSTRACT FROM AUTHOR]

The present study aims to explore the diversity patterns of cultivable filamentous fungi and establish the ecological interactions that occur within the mycological community on soapstone in two distinct places: Architectural Complex of Caraça and Congonhas town, in Minas Gerais state, Brazil. A total of 200 isolates of filamentous fungi were detected and 72 distinct taxa were identified using molecular tools. The rock-inhabiting fungal communities were comprised of cosmopolitan taxa, which displayed high diversity and richness, but low dominance indexes at two of the sampling sites over the course of 12 months. The detection of organic acids secreted by the isolated filamentous fungal species revealed the potential for deterioration of the model stone by these fungi. Our results suggest that the isolated fungal communities of the two Brazilian localities have the ability to adapt to environmental adversities over the four seasons of the year, predicting adaptive population dynamics in the stone colonization. We conclude that this study on the ecological dynamics of the rock-inhabiting fungal communities can help to understand the competitive interactions between the environmental fungi. In addition, these fungi may contribute to the preservation of the Brazilian historical heritage that is vulnerable to environmental conditions. [ABSTRACT FROM AUTHOR]

In contrast to Nordic countries, talc-rich rocks (massive and schistose talc-bearing rocks-talcite, magnesite-talc schists, chlorite-talc schists, and/or chlorite-actinolite-talc schists often loosely classified as soapstone) represented practically an unknown natural building and sculptural stone in the Czech Republic. This extraordinary material was quarried and used in the only region of the Czech Republic where Sobotín amphibolite massif (Šumperk district, northern Moravia) outcrops. Metamorphosed basic igneous rocks contain small lenses of soapstone that were exploited in the past and used not only for refractory purposes but also as a construction and sculptural material.Occurrences of 'Sobotín' soapstone show distinct zone macrofabric marked by the occurrence of massive soapstone in the core that gradually changes to talc-dominant schists, later to actinolite/tremolite-rich schists and finally to chlorite schists at the contact with surrounding amphibolites. The most typical 'Sobotín' soapstone exhibits high density (up to 2,900 kg m), low water uptake (maximum 0.68 wt %), favorable dynamic elastic properties (P-wave velocity 5,340-5,840 m s, S-wave velocity 2,900-3,300 m s), and mechanical properties (tensile splitting strength 5.2-6.9 MPa, uniaxial compressive strength 17.5-24.1 MPa). 'Sobotín' soapstone is relatively resistant to weathering action although schistose varieties show typical delamination when exposed to frequent freeze/thaw cycling in harsh mountainous environment. Field survey of monuments, architectural and building artefacts made from 'Sobotín' soapstone contributed to our knowledge on duration of exploitation of 'Sobotín' soapstone that was for sure utilised from the second half of seventeen century till the beginning of the twenty century. The most characteristic feature of 'Sobotín' soapstone is its strict local use on the territory of about 20 villages surrounding previously exploited soapstone lenses. [ABSTRACT FROM AUTHOR]

The Chumash Indians of southern California were active social agents after European contact, making choices in the traditions that they maintained despite drastic transformations in their daily lives. Archaeological and ethnohistorical evidence suggests that they continued to hold large ceremonial feasts with massive quantities of traditional foods prepared in oversized vessels, such as decorated mortars and steatite cooking pots. Many of these vessels proliferated or became more elaborate after the introduction of metal tools. The persistence and elaboration of traditional patterns of food procurement, preparation, and consumption served as a symbol of cultural identity among the Chumash and a means of maintaining and expanding social networks that extended over a wide region of California. [ABSTRACT FROM AUTHOR]

The changes in the dielectric properties of steatite ceramic before and after irradiation were studied. The characteristic vibrational frequency ω affects the change in the properties of the ceramic, which is important for devices operating in the presence of radiation. It was found that the permittivity of ceramic increased after irradiation. The structure of the material and the sintering temperature of the ceramic determine the relaxation region of the material. [ABSTRACT FROM AUTHOR]

A scarab found in grave 25 of the Monte Prama necropolis, near Cabras, Oristano, Sardinia, is of special importance for the archaeological interpretation and dating of this important archaeological site. The object has been misinterpreted in the past as composed by bone: recent archaeometric analyses showed that it is a glazed steatite of Egyptian origin and that the altered surface contains interesting phases crystallized during the high-temperature interaction of the Mg-rich talc core with the alkali-rich glass used for glazing. A novel single crystal X-ray diffraction analysis of one of the phases indicates that it is a new compound having the milarite-osumilite structure type, with a peculiar composition close to (NaK□)(Mg)(MgCuFe)(SiAl)O, not reported for naturally occurring minerals. The structural and crystal chemical features of the compound, together with the known high-temperature stability of the series, allow a complete interpretation of the glazing process and conditions, based on direct application of the glaze on the steatite core with subsequent treatment at temperatures above 1000 °C. [ABSTRACT FROM AUTHOR]

The paper summarises the results of a study by the Geological Survey of Finland on the potential use of waste rocks from natural stone quarry production. Petrographic, chemical, mechanical and physical tests were undertaken on granite, rapakivi granite, migmatite, syenite, diorite, gabbro, anorthosite gabbro, schist and soapstone from 33 dimension stone quarries in Finland. The results indicate the waste rocks of Finnish natural stone quarries can generally be considered environmentally sound with potential uses in other industries. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the diffuse reflection spectra and the difference spectra of irradiated SK-1 steatite ceramic. The study used a conventional optical method based on studying optical absorption spectra. It showed an increase in the coloration density of the ceramic as the dose increases. It also found the decomposition of the visible-range spectrum using the Origin and MathCad computer programs.