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Since their discovery in 1960 1 , metallic glasses based on a wide range of elements have been developed 2 . However, the theoretical prediction of glass-forming compositions is challenging and the discovery of alloys with specific properties has so far largely been the result of trial and error 3 – 8 . Bulk metallic glasses can exhibit strength and elasticity surpassing those of conventional structural alloys 9 – 11 , but the mechanical properties of these glasses are critically dependent on the glass transition temperature. At temperatures approaching the glass transition, bulk metallic glasses undergo plastic flow, resulting in a substantial decrease in quasi-static strength. Bulk metallic glasses with glass transition temperatures greater than 1,000 kelvin have been developed, but the supercooled liquid region (between the glass transition and the crystallization temperature) is narrow, resulting in very little thermoplastic formability, which limits their practical applicability. Here we report the design of iridium/nickel/tantalum metallic glasses (and others also containing boron) with a glass transition temperature of up to 1,162 kelvin and a supercooled liquid region of 136 kelvin that is wider than that of most existing metallic glasses 12 . Our Ir–Ni–Ta–(B) glasses exhibit high strength at high temperatures compared to existing alloys: 3.7 gigapascals at 1,000 kelvin 9 , 13 . Their glass-forming ability is characterized by a critical casting thickness of three millimetres, suggesting that small-scale components for applications at high temperatures or in harsh environments can readily be obtained by thermoplastic forming 14 . To identify alloys of interest, we used a simplified combinatorial approach 6 – 8 harnessing a previously reported correlation between glass-forming ability and electrical resistivity 15 – 17 . This method is non-destructive, allowing subsequent testing of a range of physical properties on the same library of samples. The practicality of our design and discovery approach, exemplified by the identification of high-strength, high-temperature bulk metallic glasses, bodes well for enabling the discovery of other glassy alloys with exciting properties. Bulk metallic glasses made from alloys of iridium, nickel, tantalum and boron are developed by combinatorial methods, with higher strength at high temperature than those previously produced.

Seventeen glass vessels and twenty glass beads recovered from the excavations at the ancient city of Malindi and the archaeological site of Mambrui in Kenya, east Africa were analysed using electron probe microanalysis (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The results show that all of the glass samples are soda-lime-silica glass. They belong to the high alumina -plant ash glass type, characterised by high alumina and relatively low calcium contents, widely distributed in eastern (10.sup.th - 16.sup.th centuries AD) and southern Africa (13.sup.th - 15.sup.th centuries AD), Central Asia (9.sup.th - 14.sup.th centuries AD) and southeast Asia (12.sup.th - 13.sup.th centuries AD), made with plant ashes and sands. This is an understudied glass type for which previous research has indicated there were three types. When compared with published research on such glasses using Zr, Ti, Ba, Cr, La, Li, Cs, Na.sub.2 O, MgO and CaO we have identified at least four different compositional groups of v-Na-Al glass: Types A, B, C and D. By comparing the results with contemporary v-Na-Al glass vessels and beads from Central Asia, Africa, and southeast Asia we show that most of the Malindi and Mambrui glass share similar characteristics to the compositions of Mapungubwe Oblate and some of the Madagascar glass beads from southern Africa. They belong to Type A v-Na-Al glass which is characterised by an elevated level of Ti and Ba and a relatively high ratios of Cr/La, relatively low Zr concentrations and low ratios of Zr/Ti. Differences in Zr, Li, MgO and Na.sub.2 O concentrations in Type A glass indicates that there are subgroups which might derive from different glass workshop(s) specialising in Type A v-Na-Al glass production. Comparison with the chemical compositions of glass from Ghazni, Afghanistan and Termez, Uzbekistan, and by using lead isotope analysis, we suggest v-Na-Al glass was manufactured in Central Asia and possibly worked into vessels and beads there.

Two Venetian bowls in the collection of Victoria and Albert Museum are decorated with marital arms, both with the same arms on the right (the male's) side but different ones on the left (the female's) side. Unpublished documents in the Archivio di Stato of Florence make it possible to identify these as marriages of two men of the Guidacci family, Girolamo's with Zanobia del Nero in 1486, and his son Antonio's with Maddalena da Barberino in 1515. Girolamo died in 1490; Antonio probably in 1538.

A persistent aphorism in glass studies asserts that Venetian laws provided for the death penalty for expatriate Murano glassmakers. But is it true? Already in one of the first chapters of the Capi-tulare de fiolariis of 1271, the first statute about Murano glassmaking that has come down, a fine was established for every member of the glassmakers' guild who left Venice to exercise this art. Over the following centuries, measures against the exodus of glassmakers from Venice and the release of materials suitable for glass processing were repeated. After the invention of cristallo, the provisions for the defense of the glassmaking industry gradually became stricter. In the mid-eightcenth century, the Inquisitori di Stato of Serenissima were allowed to take all the initiatives they deemed necessary, even the elimination of the most dangerous expatriates. But one can count on one hand the number of death sentences issued by the Inquisitors, and of these no more than two were carried out.

De Twee Rozen glasshouse was one of the best-known glasshouses in seventeenthcentury Amsterdam and an important producer of glass in the Venetian style. It occupied two sites: initially at Keizersgracht, from 1621, it then moved in 1657 to Rozengracht, further from the center of the city. Production debris recovered from a deposit close to the Keizersgracht site were originally attributed to an earlier glasshouse, but a reinterpretation in light of more recent excavations firmly attributes these glasses to the first location of De Twee Rozen. We present 50 new SEM-EDS analyses of vessel glass, moils, trim-offs, unfinished objects, and production waste from the later site at Rozengracht and compare these with previously published analyses from both sites. Several changes in glass technology appear to have been introduced following the change of location. First, a cristallo-type technology, involving the purification of ashes to produce a glass with lower Fe O, appears to have been used exclusively at Rozengracht. Thus, the introduction of glass production in the Venetian style was not accompanied by the signature Venetian glassmaking technology, which seems to have followed later. Second, the relatively new method of opacification using antimony was introduced, along with other changes, such as the introduction of lead into the cobalt-blue glass used in polychrome decorative canes. The origins of these new technologies are discussed in particular in view of the presence of the chemist Johann Rudolf Glauber at De Twee Rozen and its direction by a Venetian master, Nicalao Stua, from 1667.

We use computer simulations to study the thermodynamic properties of a glass-former in which a fraction c of the particles has been permanently frozen. By thermodynamic integration, we determine the Kauzmann, or ideal glass transition, temperature [Formula] at which the configurational entropy vanishes. This is done without resorting to any kind of extrapolation, i.e., [Formula] is indeed an equilibrium property of the system. We also measure the distribution function of the overlap, i.e., the order parameter that signals the glass state. We find that the transition line obtained from the overlap coincides with that obtained from the thermodynamic integration, thus showing that the two approaches give the same transition line. Finally, we determine the geometrical properties of the potential energy landscape, notably the T - and c dependence of the saddle index, and use these properties to obtain the dynamic transition temperature [Formula]. The two temperatures [Formula] and [Formula] cross at a finite value of c and indicate the point at which the glass transition line ends. These findings are qualitatively consistent with the scenario proposed by the random first-order transition theory. Significance Confirming by experiments or simulations whether or not an ideal glass transition really exists is a daunting task, because at this point the equilibration time becomes astronomically large. Recently it has been proposed that this difficulty can be bypassed by pinning a fraction of the particles in the glass-forming system. Here we study numerically a liquid with such random pinned particles and identify the ideal glass transition point [Formula] at which the configurational entropy vanishes, thus realizing for the first time, to our knowledge, a glass with zero entropy. We find that as the fraction of pinned particles increases, the [Formula] line crosses the dynamical transition line, implying the existence of an end point at which theory predicts a new type of criticality.

This article presents an assemblage of 36 glass samples excavated in the urban site of San Esteban, part of the arrabal of Arrixaca (Murcia) (in al-Andalus, an arrabal was a relatively dense urbanised area outside the city walls) in contexts securely dated to the 12th and early 13th century, spanning the rule of Ibn Mardanīš, and the early period of Almohad domination in the city. The samples were analysed by electron microprobe (EMPA) for major and minor elements and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for trace elements. The results are examined within the context of glass production, circulation, and consumption in al-Andalus and the Islamicate Mediterranean more broadly. The results show that some of the glasses found in San Esteban-Arrixaca may have been imported from other Islamicate regions (Egypt and Mesopotamia), but that the vast majority can be related to previously recognised compositional Iberian glass groups. At the same time, the identification of several fragments of production waste and raw glass suggest that some glass-working facility may have existed in the vicinity of San Esteban-Arrixaca. The compositional evidence also indicates that recycling (including of imported glass objects) may have been a fairly common practice in Andalusi glassmaking, but it is suggested that some of the usual chemical markers of recycling may, in the case of al-Andalus and perhaps also elsewhere in the medieval Mediterranean, be the result of the cross-breeding of glass- and glaze-making activities.