in this essay, jelinki pottery (clinky- ware ceramics) has been studied as one types of ceramics at arsacides era. raw materials, quality of processing and baking conditions of potteries are some of effective factors in strength and stability of this material. employing purposeful methods of chemical analyses in order to examine such factors and in fact structural science of historical potterie...

Introduction: Enstatite whiskers (<10 µm length, <200 nm width) occur in chondritic-porous interplanetary dust particles (CP IDPs) [1], an Antarctic micrometeorite [2] and a comet 81P/Wild-2 sample [3]. The whiskers are typically elongated along the [100] axis and contain axial screw dislocations, while those in terrestrial rocks and meteorites are elongated along [001]. The unique crystal morp...

Introduction: The two groups of enstatite chondrites (EH and EL) and aubrites, their differentiated counterparts, are a unique suite of specimens that formed under highly reducing conditions within the solar nebula, possibly on three separate parent bodies [1]. The reduced nature of the meteorites is shown by their unusual mineralogy, characterised by the presence of abundant sulphides. They al...

A suite of 47 carbonaceous, enstatite, and ordinary chondrites are examined for Re-Os isotopic systematics. There are significant differences in the Re/Os and Os/Os ratios of carbonaceous chondrites compared with ordinary and enstatite chondrites. The average Re/Os for carbonaceous chondrites is 0.392 0.015 (excluding the CK chondrite, Karoonda), compared with 0.422 0.025 and 0.421 0.013 for or...

Ten reversed brackets of aqueous silica concentration in equilibrium with enstatite (Mg2Si2O6) and forsterite (Mg2SiO4) were determined at 700 to 900°C and 4.35 to 14 kbar. Silica solubilities were measured by a weight loss-weight gain method and by approaching equilibrium from higher and lower silica concentrations. Both single-crystal and fine-grained synthetic enstatite and forsterite starti...

The mechanical properties of steatite ceramics after high-temperature processing depend on inversion of high-temperature Mg2Si2O6 protoenstatite polymorph to low clinoor ortho-enstatite, which are characterized by Raman spectroscopy. The Raman spectrum of a pure Mg2Si2O6 protoenstatite is sufficiently distinct from those of low clinoand ortho-enstatite to allow rapid identification in a bulk sa...

sepiolite deposits have been recently discovered in northeastern iran. however, there is still little information about its physicochemical and mineralogical characteristics. therefore, the collapse of the sepiolite (with sizes of < 63 μm) structure induced by temperature elevation in an electric furnace at 350, 550, and 850 °c for 4 hours was studied using x-ray diffraction (xrd) in combinatio...