Abstract: A dental prosthesis may be cast and machined from a cobalt-, iron- and/or nickel-chromium base dental alloy comprising at least 25% metal selected from the group consisting of ruthenium, platinum, palladium, iridium, osmium, rhodium, and gold wherein the major portion or at least 15%, whichever is larger, of metal in this group is ruthenium; from 15 to 30% chromium; and a principal balance of metal selected from the group consisting of iron. nickel and cobalt.

Abstract: The sputtering target made of a Ag—Bi-base alloy contains Bi in solid solution with Ag. The sputtering target has an intensity of precipitated Bi of 0.01 at %?1 or less, as calculated by the following mathematical expression (1) based on analysis results of X-ray diffraction, and/or a sum of area ratios of predetermined intensities (third to sixth intensities in 8 intensities) of 89% or more, wherein the area ratios are obtained by calculating a planar distribution of characteristic X-ray intensities of Bi according to X-ray microanalysis: intensity of precipitated Bi=[IBi(102)/IAg(111)+IAg(200)+IAg(220)+IAg(311))]/[Bi]. Remarkable lowering of the yield of Bi content in resultant films can be suppressed by using the sputtering target.

Abstract: The invention relates to a high-hardness palladium alloy for manufacturing semi-finished products to be used in goldsmith's art or jewels to be obtained by the lost wax casting method, which comprises, in the following concentrations, expressed in thousandths by weight (‰): palladium from 948 to 990‰; copper from 0.0 to 50‰; indium from 0.0 to 50‰; gallium from 1 to 48‰; aluminium from 0.8 to 49.5‰; ruthenium from 0.0 to 50‰; rhenium from 0.0 to 50‰; silicon from 0.1 to 1.2‰; platinum from 0.0 to 40‰; nickel from 0.0 to 50‰; iridium from 0.0 to 40‰. In the manufacturing process of the above alloy, the component elements of said alloy are placed in a crucible, respectively made of zirconia, boron nitride or other ceramic material, and are melted using the induction method and using a protective atmosphere, respectively of argon, nitrogen or other inert gas.

Abstract: An alloy for use in jewelry applications is provided that has a composition comprising about 45 to about 55 platinum by weight and about 55 to about 45 percent palladium by weight. The alloy possesses favorable characteristics as compared to pure platinum and pure palladium. Due to these characteristics, the alloy is attractive for use in jewelry applications.

Abstract: A wire, strip or reshaped part is produced from an alloy based on platinum, palladium or a mixture of platinum and palladium and hardened by oxide dispersion. The wire, strip or reshaped part cross-section exhibits a peripheral zone in which at least one relatively easily volatilized oxide generator is depleted by at least 25%. In addition, a process is provided for production of such a wire, strip or reshaped part, in which a porous skin is produced thermally on the wire, strip or reshaped part, and the porous skin is compacted by conversion into a soft or impermeable skin.

Abstract: Gold solder compositions for assembling, repairing and sizing jewelry containing about 85% to 95% by weight palladium and an alloy mixture containing about 5% to 15% gallium and indium, in a weight ratio of approximately 7:3. The invention also provides a solder composition for assembling, repairing and sizing jewelry containing white gold and palladium, but not containing nickel. Such a solder contains gold, silver, copper, zinc, palladium, gallium and indium, whereby the gallium and indium is in a weight ratio of 6:4, 7:3 or 8:2, respectively.

Abstract: A method for repairing an article comprises providing an article, providing a repair material, and joining said repair material to said article. The repair material comprises, in atom percent, at least about 50% rhodium; up to about 49% of a first material, said first material comprising at least one of palladium, platinum, iridium, and combinations thereof; from about 1% to about 15% of a second material, said second material comprising at least one of tungsten, rhenium, and combinations thereof; and up to about 10% of a third material, said third material comprising at least one of ruthenium, chromium, and combinations thereof. The repair material comprises an A1-structured phase at temperatures greater than about 1000° C., in an amount of at least about 90% by volume.

Abstract: The present invention relates to a process for the production of continuous silver wires having micrometric or sub-micrometric diameter comprising a step of thermal decomposition of silver dodecyl-mercaptide in the presence of metallic aluminum.

Abstract: An iridium-based alloy which has L12-type intermetallic compounds dispersedly precipitated therein and has a basic composition including, in terms of mass proportion, 0.1 to 9.0% Al, 1.0 to 45% W, and Ir as the remainder. The component system containing 0.1 to 1.5% Al has L12-type intermetallic compounds dispersedly precipitated therein. The component system containing 1.5 to 9.0%, excluding 1.5%, Al has L12-type and B2-type intermetallic compounds dispersedly precipitated therein. Part of the Ir may be replaced with an element (X) (Co, Ni, Fe, Cr, Rh, Re, Pd, Pt, or Ru) and part of the Al and W may be replaced with an element (Z) (Ni, Ti, Nb, Zr, V, Ta, Hf, or Mo). The iridium-based alloy, which contains L12-type intermetallic compounds [1r3(Al,W) and [(Ir, X)3(Al, W, Z)] dispersedly precipitated therein, has a high melting point. The lattice constant mismatch between the L12-type intermetallic compounds, i.e.

Abstract: A durable Pd-based alloy is used for a H2-selective membrane in a hydrogen generator, as in the fuel processor of a fuel cell plant. The Pd-based alloy includes Cu as a binary element, and further includes “X”, where “X” comprises at least one metal from group “M” that is BCC and acts to stabilize the ? BCC phase for stability during operating temperatures. The metal from group “M” is selected from the group consisting of Fe, Cr, Nb, Ta, V, Mo, and W, with Nb and Ta being most preferred. “X” may further comprise at least one metal from a group “N” that is non-BCC, preferably FCC, that enhances other properties of the membrane, such as ductility. The metal from group “N” is selected from the group consisting of Ag, Au, Re, Ru, Rh, Y, Ce, Ni, Ir, Pt, Co, La and In. The at. % of Pd in the binary Pd—Cu alloy ranges from about 35 at. % to about 55 at. %, and the at. % of “X” in the higher order alloy, based on said binary alloy, is in the range of about 1 at. % to about 15 at. %.

Abstract: An object of the present invention is to provide a material for a precious metal tip of a spark plug, which has more excellent durability, particularly oxidation wear resistance than a conventional one. The precious metal alloy for the spark plug according to the present invention contains 0.2 to 6.0 wt. % Cr as an essential component, further at least any one of Fe or Ni, and the balance being Ir. Here, the amount of Fe and Ni to be added is preferably 2.0 to 12.0 wt. % in total. According to the present invention, the surface may be oxidized to form an oxide layer made from a Cr—Fe oxide, a Cr—Ni oxide or a Cr—Fe—Ni oxide. The oxide layer is formed by a diffusion treatment by heating the precious metal alloy at 300 to 900° C. in an oxidative atmosphere, and preferably has a thickness of 5 to 100 ?m.

Abstract: Pt-based bulk-solidifying amorphous alloys and methods of forming articles from Pt-based bulk-solidifying amorphous alloys are provided. The Pt-based alloys of the current invention are based on Pt—Ni—Co—Cu—P alloys.

Abstract: The present invention is a silver alloy including silver as the main component and at least one rare-earth element as a first dopant element, and excellent in reflectance maintenance property. In the present invention, the first dopant element is preferably samarium, neodymium, lanthanum, cerium, ytterbium, terbium, dysprosium, holmium, erbium, thulium, europium, and gadolinium. Also, in the present invention, the silver alloy preferably includes, as a second dopant element, at least one element selected from copper, manganese, silicon, chromium, nickel, cobalt, yttrium, iron, scandium, zirconium, niobium, molybdenum, tantalum, tungsten, platinum, gold, rhodium, iridium, palladium, indium, tin, lead, aluminum, calcium, gallium, bismuth, antimony, strontium, hafnium, and germanium.

Abstract: The problem is to provide an Au—Sn alloy powder for use in producing an Au—Sn alloy solder paste having reduced generation of voids. The problem is solved by an Au—Sn alloy powder for a solder paste, which has a composition consisting of Sn of 20.5-23.5% by mass and a remainder containing Au and inevitable impurities, and which has a microstructure in which 0.5 to 30 area % of fine Sn-rich primary crystal phase regions having a diameter of 3 ?m or less are crystallized in a matrix.

Abstract: The present invention relates to an Ag alloy film. Particularly, it is preferably used as a reflective film or semi-transmissive reflective film for an optical information recording medium having high thermal conductivity/high reflectance/high durability in the field of optical information recording media, an electromagnetic-shielding film excellent in Ag aggregation resistance, and an optical reflective film on the back of a reflection type liquid crystal display device, or the like. The Ag alloy film of the present invention comprises an Ag base alloy containing Bi and/or Sb in a total amount of 0.005 to 10% (in terms of at %). Further, the present invention relates to a sputtering target used for the deposition of such an Ag alloy film.

Abstract: The present invention includes an apparatus, system and method for screening and making one or more electrocatalysts, electrocatalyst arrays, electrodes and catalysts for an oxygen reduction reaction with a Group VIII noble metal in contact with a component-M o form a Group VIII noble metal-M alloy, wherein component-M is one or more metals selected from Groups IIIA, IVA, VIII, IB, IIB, VB, VIB, VIIB and VIIIB of the Periodic Table.

Abstract: A fine silver particle powder is provided that is a suitable material for interconnects used to form fine circuit patterns especially by the inkjet method, and a method of manufacturing the powder. Although the powder is fine and therefore has a large specific surface area, it has good weatherability and corrosion resistance. The powder particles have a calculated specific surface area (CS) of 50 m2/cm3 or more, an X-ray crystal grain diameter (DX) of not more than 50 nm, not more than 10.0 basicity points/nm2 and not more than 10.0 acidity points/nm2. To obtain the silver particle powder, a silver compound is reduced in an organic solvent, using as the reducing agent one, two or more selected from an alcohol or polyol. The reduction reaction proceeds in the presence of an organic protective agent and a polarity inhibition agent.

Abstract: Provided is a sputtering target material which has a high reflectance and which is excellent in a sulfurization resistance, comprising an Ag alloy prepared by alloying Ag with a specific small amount of the metal component (A) selected from In, Sn and Zn, a specific small amount of the metal component (B) selected from Au, Pd and Pt and, if necessary, a small amount of Cu.

Abstract: A wire, strip or reshaped part is produced from an alloy based on platinum, palladium or a mixture of platinum and palladium and hardened by oxide dispersion. The wire, strip or reshaped part cross-section exhibits a peripheral zone in which at least one relatively easily volatilized oxide generator is depleted by at least 25%. In addition, a process is provided for production of such a wire, strip or reshaped part, in which a porous skin is produced thermally on the wire, strip or reshaped part, and the porous skin is compacted by conversion into a soft or impermeable skin.

Abstract: A composition for use as a catalyst in, for example, a fuel cell, the composition comprising platinum, copper and tungsten, or an oxide, carbide and/or salt of one or more of platinum, copper and tungsten, wherein the sum of the concentrations of platinum, copper and tungsten, or an oxide, carbide and/or salt thereof, is greater than 90 atomic percent.

Abstract: Improved 14-karat rose-colored gold alloy compositions include: about 58.5% gold; about 9.0-12.0% silver; about 0.0-0.2% zinc; about 0.3-0.4% cobalt; about 0.0-0.02% iridium; and about 29.0-33.0% copper. Improved 18-karat rose-colored gold alloy compositions include: about 75.2% gold; about 7.0% silver; about 0.0-0.2% zinc; about 0.3-0.4% cobalt; about 0.0-0.02% iridium; and about 17.0-17.5% copper. The hardness of these compositions are capable of being selectively changed between their respective annealed-hardness and age-hardness values. The color of these compositions is between about 5-7 CieLab a* color units and between about 17-21 CieLab b* color units.

Abstract: The present invention provides a silver alloy for use in a reflection film in an optical recording medium, comprising silver as a main component, and at least one metal element as a first additive element having lower melting point than that of silver. Preferable first additive elements in the present invention are aluminum, indium, tin, bismuth, gallium, zinc, strontium, calcium and germanium. Further, second additive elements in the present invention are preferable if they contain at least one of elements comprising platinum, gold, rhodium, iridium, ruthenium, palladium, lead, copper, manganese, silicon, nickel, chrome, cobalt, yttrium, iron, scandium, zirconium, titanium, niobium, molybdenum, tantalum, tungsten, hafnium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, thulium, ytterbiumm, magnesium, and boron.

Abstract: The disclosure relates to a platinum alloy comprising (a) 55 to 63 wt. % of platinum, (b) 2 to 10 wt. % of cobalt, and (c) 27 to 43 wt. % of copper. The disclosure further relates to a platinum alloy comprising (a) 70 to 79.5 wt. % of platinum, 2 to 10. wt. % of cobalt, and (c) 10.5 to 28 wt. % of copper. The platinum alloys have excellent mechanical and optical properties for use in the production of ornamental articles such as rings, necklaces, earrings, watch bands, watch bodies and other jewelry. The disclosure further relates to a method of preparing the platinum alloys and their use in the production of ornamental articles. Still further the disclosure relates to ornamental articles comprising the platinum alloy and a method of production thereof.

Abstract: A method of manufacturing a hard precious metal alloy member comprising casting a material consisting essentially of a gold alloy, which has a gold content of from 37.50 to 98.45 wt %, and contains gadolinium in an amount of not less than 50 ppm, but less than 1,5000 ppm; subjecting the material to a solution heat treatment; and subjecting the material to an aging treatment after the solution heat treatment.

Abstract: Gold bonding wires for semiconductor devices featuring increased strength and modulus of elasticity, stable loop shapes, suppressing the flow of wires, suppressing the leaning, and totally improved junctions of the wedge junction portions or wear characteristics for realizing a narrow-pitch connection, and enhanced the productivity on an industrial scale, and a method of producing the same. A gold bonding wire for a semiconductor device has a crystal grain structure in cross section in the lengthwise direction of the bonding wire, wherein a ratio of the area of crystal grains having an orientation [111] to the area of crystal grains having an orientation [100] is not smaller than 1.2 in the crystal orientations in the lengthwise direction of the wire.

Abstract: Nanometer to micrometer sized particles containing platinum and having selected morphologies are prepared by a sonochemical process. A compound of platinum is dissolved, suspended, or diluted in a suitable liquid medium at a predetermined concentration and the liquid is maintained at a predetermined temperature from sub-ambient temperatures to above ambient temperatures. A reducing gas is bubbled through the liquid as it is subjected to cavitation at a controlled power to affect the reductive decomposition of the platinum compound. The morphology of the precipitated platinum particles can be varied widely by varying the described concentration, temperature and power parameters.

Abstract: A palladium-boron composition and methods of making and using same are provided. In one aspect, the invention comprises an alloy comprising palladium and boron, the boron being in solid solution in the palladium and the alloy having a two-phase structure, wherein each phase of the two-phase structure has the same crystal structure as the other phase and has a different set of lattice parameters from the other phase such that the palladium is greatly hardened by the presence of the smaller phase crystals within the spaces between the larger phase crystals. The composition is carefully prepared by a process wherein palladium and an amount of boron sufficient to place the boron in solid solution, but insufficient to combine with the palladium, are placed together and repeatedly are melted, cooled and turned over until sufficiently mixed.

Abstract: A method for making dendritic metal nanostructures using a surfactant structure template, a metal salt, and electron donor species.

Abstract: A family of alloys for use in medical, electrical contact and jewelry applications includes as primary components palladium, and boron and at least one of ruthenium, rhenium, platinum, gold, zirconium, tungsten, cobalt, nickel, tantalum and iridium. An alternative embodiment includes palladium and rhenium and/or ruthenium with an additional element iridium, platinum, tungsten, boron, gold, zirconium, cobalt, nickel and tantalum. The present alloy family has a high strength, high radio opacity, and biocompatibility characteristics, while also being workable into various configurations. Where required, some of the alloys also offer post form, heat treatment (age hardening) capabilities for even higher hardness and strength levels.

Abstract: Alloy compositions, including devices and instruments that include the compositions, are disclosed. The compositions have high hardness, strength, corrosion resistance, and biocompatibility. The compositions can be used to manufacture, for example, medical devices and products.

Abstract: Timepiece or jewelry part manufactured in an alloy containing at least 75% gold by weight, from 21% to 23% copper by weight, and from 1% to 4% platinum by weight.

Abstract: Dental prostheses are machined from a metallic body instead of being made by lost wax casting. Suitable gold base alloys have only base metal alloying additions which are more readily oxidized than gold and when combined with the gold can be age hardened. Exemplary metals include titanium, zirconium, yttrium and chromium. Scrap from the machining of a dental prosthesis is melted in air so that the base metals are all oxidized and substantially pure gold is reclaimed for reuse in new alloys.

Abstract: The present invention provides nanoprisms etched to generate triangular framework structures. These triangular nanoframes possess no strong surface plasmon bands in the ultraviolet or visible regions of the optical spectrum. By adding a mild reducing agent, metal ions remaining in solution can be reduced, resulting in metal plating and reformation of nanoprisms. The extent of the backfilling process can be controlled, allowing the formation of novel nanoprisms with nanopores. This back-filling process is accompanied by a regeneration of the surface plasmon bands in the UV-visible spectrum.

Abstract: A precious metal sputter target has a composition selected from the group consisting of platinum, palladium, rhodium, iridium, ruthenium, osmium and single-phase alloys thereof. The sputter target's grain structure is at least about 99 percent recrystallized and has a grain size of less than about 200 ?m for improving sputter uniformity. The cryogenic method for producing these sputter targets is also effective for improving sputter performance for silver and gold sputter targets.

Abstract: A manganese alloy sputtering target characterized in that oxygen is 1000 ppm or less, sulfur is 200 ppm or less and a forged texture is provided, and a method for producing a forged manganese alloy target stably by eliminating the drawbacks of manganese alloy that it is susceptible to cracking and has a low rupture strength. A manganese alloy sputtering target which can form a thin film exhibiting high characteristics and high corrosion resistance while suppressing generation of nodules or particles is thereby obtained.

Abstract: A sterling silver alloy composition of exceptional and reversible hardness and enhanced tarnish resistance, consists essentially of the following parts by weight: at least about 92.5% silver; about 4.4% to about 5.25% copper; about 0% to about 1.0% zinc; about 0.85% tin; about 0.05% to about 0.3% lithium; about 0.05% to about 0.5% silicon; about 0% to about 1.2% germanium; and about 0% to about 0.02% boron.

Abstract: Platinum, silver and gold solder compositions for repairing, assembling, or sizing jewelry. Platinum compositions having about 90% to about 95% by weight platinum. Silver compositions having at least 92.5% by weight silver. Gold solder compositions having about 25% to about 91.6% gold. The platinum and silver solder compositions further consisting of about 8.3% to about 75% by weight of an alloy consisting essentially of gallium, indium and copper in respective ratios of 6:3:1. The gold solder compositions further consisting of about 2% to about 14% by weight of an alloy consisting essentially of gallium, indium, and copper in respective ratios of 6:3:1. The melting temperature ranges of the respective solder compositions are from about 1300° C. to about 1500° C. for platinum, from about 1000° F. to about 1400° F. for silver, and from about 1100° F. to about 1550° F.

Abstract: A nickel-free white gold alloy composition having selectively reversible hardness characteristics between its annealed- and aged-hardness values, consists essentially of: about 55–60% gold; about 6.0–10.0% palladium; about 5.0–12.0% copper; about 0.1–2.0% zinc; and about 20–30% silver. A 14-karat nickel-free white gold alloy composition, consists essentially of: about 58.5% gold; about 25.0–27.15% silver; about 6.0% palladium; about 5.0–12.0% copper; about 0–2.0% zinc; about 0–0.2% cobalt; about 0–0.005% iridium; and about 0–0.01% lithium.

Abstract: The invention is a novel photo-induced method for converting large quantities of silver nanospheres into nanoprisms, the nanoprisms formed by this method and applications in which the nanoprisms are useful. Significantly, this light driven process results in a colloid with a unique set of optical properties that directly relate to the nanoprism shape of the particles. Theoretical calculations coupled with experimental observations allow for the assignment of the nanoprism plasmon bands and the first identification of two distinct quadrupole plasmon resonances for a nanoparticle. Finally, unlike the spherical particles from which they derive and which Rayleigh light scatter in the blue, these nanoprisms exhibit scattering in the red, permitting multicolor diagnostic labels based not only on nanoparticle composition and size but also on shape.

Abstract: A unique manganese silver alloy composition is provided, which alloy exhibits the long desired properties of exceptional as-cast hardness and reversible heat treatability, in addition to offering reduced fire scale, reduced voids and porosity, reduced grain size, and reduced oxide formation when heated consisting essentially of the following parts by weight: about 92.5–92.8% silver, about 2.0–3.0% copper, about 2.0–3.0% zinc, about 0.03–0.05% indium, about 0.01–0.03% tin, about 0.20–0.50% boron/copper alloy (22% boron, 98.0% copper) about 0.50–0.90% silicon/copper alloy (10.0% silicon, 90.0% copper), and 0.01%–0.10% manganese “30” (0.30% of a manganese-copper alloy containing about 30% manganese and about 70% copper).

Abstract: A silver-platinum alloy formulated to provide improved tarnish resistance and hardness as compared to sterling silver. The alloy can be incorporated in various jewelry, flatware, and like articles. The alloy generally includes silver and platinum, with silver being the predominant component. In certain applications, the alloy includes about 90–95.5% silver and about 0.5–6% platinum. A small amount of gallium can also be added to the composition to provide ease of manufacture of the alloy. The resulting alloy has the favorable properties afforded by sterling silver, but also has brighter surface finish, greater tarnish resistance and increased hardness as compared to traditional sterling silver.

Abstract: The present invention provides a processing method capable of continuously working an Au—Sn soldering metal having a foil form in room temperature. The foil-form soldering metal containing from 10% by weight to 90% by weight of Au and balance comprising Sn is subjected to heat treatment for five minutes to ten hours at 200° C. to 270° C., and subsequently the foil-form soldering metal is slit. Thus, the heat treatment of the Au—Sn soldering metal before slitting enables continuous slitting of the Au—Sn foil-form soldering metal in room temperature and facilitates the production of a ribbon-form soldering metal.

Abstract: Metal-containing nanostructured films are prepared by electrodepositing a metal-containing composition within the pores of a mesoporous silica template to form a metal-containing silica nanocomposite. The nanocomposite is annealed to strengthen the deposited metal-containing composition. The silica is then removed from the nanocomposite, e.g., by dissolving the silica in an etching solution to provide a self-supporting metal-containing nanostructured film. The nanostructured films have a nanowire or nanomesh architecture depending on the pore structure of the mesoporous silica template used to prepare the films.

Abstract: Electrically resistive material including platinum and from about 5 and about 70 molar percent of iridium, ruthenium or mixtures thereof, calculated based on platinum as 100%, are disclosed.

Abstract: An alloy and a gas turbine engine component comprising an alloy are presented, with the alloy comprising: palladium, in an amount ranging from about 1 atomic percent to about 41 atomic percent; platinum, in an amount that is dependent upon the amount of palladium, such that a. for the amount of palladium ranging from about 1 atomic percent to about 14 atomic percent, the platinum is present up to about an amount defined by the formula (40+X) atomic percent, wherein X is the amount in atomic percent of the palladium, and b. for the amount of palladium ranging from about 15 atomic percent up to about 41 atomic percent, the platinum is present in an amount up to about 54 atomic percent; and the balance comprising rhodium, wherein the rhodium is present in an amount of at least 24 atomic percent; wherein the alloy comprises a microstructure that is essentially free of L12-structured phase at a temperature greater than about 1000° C.

Abstract: A nickel- and palladium-free 14-karat white gold alloy composition consists of the following parts by weight: about 58.34% gold, about 35–40% silver, about 0.5–1.80% tin, and about 0–0.75% germanium.

Abstract: The invention includes a physical vapor deposition target composed of a face centered cubic unit cell metal or alloy and having a uniform grain size less than 30 microns, preferably less than 1 micron; and a uniform axial or planar <220> texture. Also described is a method for making sputtering targets. The method can comprise billet preparation; equal channel angular extrusion with a prescribed route and number of passes; and cross-rolling or forging subsequent to the equal channel angular extrusion.

Abstract: The present invention relates to a silver braze alloy having improved wetting properties. The silver braze alloy consists essentially of from about 52.25 wt % to about 57.0 wt % silver, from about 38.95 to about 43.0 wt % copper, from about 0.5 wt % to about 5.5 wt %, preferably from about 1.0 wt % to about 5.5 wt %, manganese, and up to about 2.5 wt %, preferably from about 1.5 wt % to about 2.5 wt %, nickel. The alloy further may contain 0.15 wt % total of other trace elements.

Abstract: A silver alloy with color fastness includes silver as major component; and a small quantity of copper, zinc and nickel so that it can be prevented to oxidize, and it can use metal with easy procurement without special metal and manufacture a alloy with color fastness.

Abstract: A jewellery alloy, having a substantially purple hue and sufficient toughness to withstand Rockwell 3 hardness testing with a 100 kg load without shattering, comprises 76 to 83.5 wt % gold and 16.5 to 21.5 wt % aluminum. In one embodiment, the alloy consists of more than 78.5 wt % gold (but not more than 83.5 wt %) and a balance or aluminium. In another embodiment, the alloy comprises an additional element selected from palladium and nickel.