New trends in the use of metals in jewellery

Abstract

Owing, on the one hand, to the constant increase in the o/os of nickel sensitization in the majority of allergy departments of dermatology and, on the other, to the fact that sensitization to nickel is almost always through contact with jewellery and imitation jewellery, an update was carried out on the metal alloys principally used in the manufacture of such jewellery (earrings, bracelets, necklaces, rings, watch straps, etc.) The conclusions of this review demonstrate that nickel is irreplaceable in the majority of the alloys, because of its excellent technical properties and low price and, as a result, the % of sensitizations to this allergen will not only maintain their present high level but will probably increase in the future.Key words: jewellery; imitation jewellery; nickel; metal alloys; industry; patents; allergic contact dermatitis. Accepted for publication 6 December 1990Nickel sensitization maintains a high profile in all allergy and contact dermatitis departments. Without doubt it is the number-one allergy, mainly affecting women. Currently, in our allergy department, the % of sensitization to nickel is 22%. Of this 22%, 20.5% is relevant and 12.5% (all women) is relevant to jewellery and imitation jewellery (earrings, rings, necklaces, watch fasteners, bracelets, etc.)The aim of this enquiry was to establish the current trends in the manufacture of jewellery and imitation jewellery, and the content of nickel and other metals in typical alloys used in this field.In the last 15 years, due to the increasingly high prices of precious metals, there has been an unceasing search for substitutes with the same physicochemical properties and beauty. This has spawned a series of investigations into ways in which precious metals can be used in smaller quantities and still preserve their characteristics of beauty and unalterability in use; and into new alloys which lower the costs of raw materials and manufacture, but retain a quality end-product suitable for its destined use. Review of Current PracticesWomen have tired of the 'same old look' of gold and silver jewellery and are demanding new products with a different style and appearance to complement fashion clothing, a fact that has led to the investigation of ways of using precious metals economically and of substituting low-cost alloys (1-11). Saving on precious metalsTo save on gold plating, thin layers of down to 0.3 11-m have been achieved which, with modem techniques, can uniformly be applied using an underlayer of brilliant nickel of differing thick-

Copper: toxicological relevance and mechanisms

“…Its malleability, low corrosion, alloying ability, high thermal conductivity, and high electrical conductivity make Cu one of the most important metals for industrial application. Cu is used as a metal or alloy in machinery, construction, transportation, and military weapons (Barceloux, 1999; Winge and Mehra, 1990) and is an important component of white gold and other alloys used for imitation jewelry, dental products, and in many cosmetics (Okereke et al, 1972; Vilaplana et al, 1991; Lucas and Lemons, 1992). Cu metal has low reactivity due to its high nuclear charge, small size, and consequent high ionization potential (Georgopoulos et al, 2006.)…”

Alergia de Contacto a Metais num Período de 20 Anos no Centro de Portugal: Implicações das Directivas Europeias

“…), próteses dentárias e ortopé-dicas. [3][4][5][6][7][8] Nos indivíduos sensibilizados, a exposição cutânea ao Ni em concentrações superiores ao limite é capaz de desencadear a DCA, o contacto com próteses metálicas or-Revista Científica da Ordem dos Médicos www.actamedicaportuguesa.com Teixeira V, et al Alergia de contacto a metais num período de 20 anos no centro de Portugal, Acta Med Port 2014 May-Jun;27(3): [295][296][297][298][299][300][301][302][303] topédicas ou dentárias poderá desencadear reações locais de intolerância e a sua absorção pode causar dermatite de contacto sistémica.…”

“…Deste modo, frequentemente a alergia ao Co acompanha a alergia ao Cr e/ou Ni, por sensibilização concomitante. [3][4][5] O crómio é um alérgeno importante do ponto de vista profissional, nomeadamente na construção civil com o manuseio do cimento, contacto com produtos de cabedal e na indústria de curtimento, como pigmento em tintas anti-corrosivas. Na exposição não profissional, salienta--se o contacto com produtos de cabedal (calçado, correias de relógio, luvas, cinto, etc.…”

Nickel and cobalt allergy before and after nickel regulation – evaluation of a public health intervention

“…To give jewellery a golden appearance, nickel may be plated with uniform layers of gold as thin as 0.3 µm (15). Items are typically covered with a transparent varnish based on acrylic resins to increase resistance against wear (15). Many other gold and nickel alloys have also been patented and used for inexpensive jewellery (15).…”

“…Items are typically covered with a transparent varnish based on acrylic resins to increase resistance against wear (15). Many other gold and nickel alloys have also been patented and used for inexpensive jewellery (15). However, gold‐plated items may release nickel as the layer of gold is thin and porous and easily cracks (14).…”