The Chemical Composition of the Medieval Mirrors from Golden Horde Time Settlements

Introduction. The paper discussed the results of the study concerning the chemical composition of 16 mirrors from the Golden Horde period originating from the settlements Selitrennoe, Vodyanskoe, Uvekskoe Khmelevskoe I, Shirokiy Buerak and stored in the State Historical Museum (Moscow) and Saratov Regional Museum of Local Lore (Saratov). Method. The visual inspection of the items was carried out using the traceology method, XRF and SEM/EDS were used as a method of determining the elemental composition. To compare the results, data on the chemical composition of mirrors originating from other medieval sites in Eastern Europe were used. Analysis and Results. All but one mirror, made with a stone casting mold, were cast using the impression method. Some of the mirrors show traces of post-casting processing. Several types of alloys have been identified. Most of the mirrors were made of tin-lead bronze (7 items) with an increased (more than 20 %) tin content, which correlates with the results obtained on samples from other settlements of the pre-Horde and Horde times. Other large groups are mirrors made from multicomponent (3 items) and tin bronze (4 items). One mirror each is made of tin brass and lead bronze with the addition of arsenic. Mirrors with arsenic in their composition are also known from other samples from a nomadic cemetery of the Golden Horde period and settlement monuments, which indicates a sufficiently active existence of a more archaic metal in the 14th century.

Current state and prospects of stone mining and stone processing waste use in silicate industries (review)

A review of foreign and native publications on the use of man-made raw materials, which is formed during the extraction and processing of rocks, in the silicate materials production was presented. It was shown that, the disposal of large-scale industrial waste from mining and ore processing industrial complexes is promising for solving environmental problems and expanding the raw material base of silicate industries. An increase in the waste consumption degree will contribute to the integrated use of mineral raw materials, as well as a decrease in the volume of their accumulation and an improvement in the environmental situation. A literature review has shown the obvious potential of waste as an alternative raw material for partial or complete replacement of traditional raw materials in various silicate industries. On the example of artificial stone, stone casting, cement, concrete, ceramic bricks and tiles production, the technologies of silicate materials and products were considered, where waste disposal is technologically sound and economically feasible. It was shown that, mineral technogenic raw materials (wastes from mining, mechanical processing and enrichment of rocks) are used as a concrete, artificial stone and other composite binder’s filler, as non-plastic and fluxing components of ceramics bodies, and even as the main raw material in the production of stone casting. On specific examples, it was considered how a reasonable rocks waste use in the silicate materials production can improve the products properties. Requirements were formulated and criteria for the applicability of stone mining and stone processing waste in the silicate materials production were determined, consideration of which will reduce the hazards and risks associated with the possible presence of technologically harmful and potentially hazardous substances in waste. Knowledge of the using peculiarities wastes from the extraction and processing of the different rocks will allow to optimize technological processes when replacing natural raw materials with technogenic materials. Providing scientific and technical information on the advantages of using waste in the ceramic, glass-crystalline, binders and composite materials production will contribute to the development of resource-saving environmentally friendly technologies, natural resources rational use and increase of industrial enterprises responsibility to society and nature.

The current status and industrial perspectives of the kyanite application in the refractory and foundry facing materials

The investigating results are given for the kyanite concentrate using in both the refractory and the facing materials for the iron founding and for the stone casting, as well as for the Investment shells in the precision steel casting.Ill.2. Ref. 20. Tab. 2.

Stonehenge and Avebury: Megalithic shadow casting at the solstices at sunrise

The paper examines how specific megaliths at Stonehenge and Avebury were positioned relative to others and to particular sunrises such as to produce watchable effects arising from solar movement and resulting lithic shadows. At Stonehenge and environs numerous research expeditions (exceeding 120 that started in 1981) combined with accurate compass analysis, photography and studies of the best plans of the sarsen-stone and bluestone phases have led to explanations for apparent anomalies of stone positioning that have not been clarified before.Firstly, at the summer solstice in the Late Neolithic the Altar Stone was illuminated by sunshine for the first three or four minutes of the day, following which the shadow of the round-topped Heel Stone was cast into the middle of Stonehenge to reach the Altar Stone. This circumstance continues to be witnessed today. It is a consequence of the Heel Stone being deliberately offset from the Stonehenge axis of symmetry. Again, there is the offset positioning of the anomalous half-height, half-width, Stone 11 that disrupts the otherwise regular arc of the lintelled sarsen circle. It is also a fact that the Altar Stone, although on the midsummer sunrise axis and bisected by it, does not lie perpendicular to the monument’s axis but is instead angled lengthways in the direction of the winter solstice sunrise. The same is true of the orientation of the Great Trilithon (as recently discussed by T. Daw). This suggests that the Altar Stone and the Great Trilithon were deliberately positioned this way in order to respect and emphasise an older arrangement in which a midwinter sunrise megalithic setting had been important. Such an arrangement involving the winter solstice sunrise still exists because the shadow of the short round-topped Stone 11 at sunrise appears aimed at the rhyolite ignimbrite Bluestones 40 and 38 - both of which are damaged, fallen and possibly parts of a single original. In similar manner the site of Hole G could indicate the former position of an ancestral stone with regard to equinoctial sunrises. Thus, these shadow-casting experiences for sunrise at Stonehenge may have affinities with the proven stone-to-stone casting of shadows for the same significant calendar dates at the carefully examined Drombeg Stone Circle. At Avebury the stones of the Cove in the northern circle together with Avebury’s Stone F harmonize likewise at the summer solstice sunrise. Two surviving megaliths in Avebury’s southern circle behave similarly. It is discussed whether an explanation in terms of the ancient worldview of the hieros gamos between Sky and Earth may be appropriate for Stonehenge and Avebury as it could also be at Drombeg.

Influence of Structural Components on Strength Properties of Silicate Stone Casting Materials during Controlled Crystallization

Study and description of positive effect influence of Cr2O3 catalyst in controlled crystallization technology for production of stone casting silicate materials are provided. The introduction of heat treatment method that influences the forming of the structural components of produced material. The basis of manufacturing stone casting silicate materials is controlled crystallization of silicate melt that is organized in such a way that nucleation occurs within the melt and the final product has a fine grain structure. The structural components of silicate stone casting materials and their influence on strength properties are determined. The strength of stone casting silicate materials is the reduction in the difference in the temperature coefficients of linear expansion of crystal phases and residual glass phase.

Composition Development and Production Technology of Stone Casting Silicate Materials and Items

Though silicate-oxide materials are in demand in all industries, inclusive of defense industry, their application is limited by manufacturing capability of their formation. Therefore, range expansion of manufacturing capability of forming silicate-oxide materials is an important issue. Casting technology allows obtaining fair-sized items and composite pattern at lower cost. It is used for silicate-oxide materials in petrurgical (stone casting) manufacturing, the melt for stone casting technology being often received by electric arc method.