> > Peter Johns
Peter Johns

Silversmith and materials scientist

Peter is a master silversmith and metallurgist. He is the inventor of Argentium® Silver.

In 1990, Peter started to research the benefits of alloying the element germanium with silver. Germanium was found to give it unique properties. Peter’s invention has been adopted worldwide.

It started with a phone call

In 1989 Peter Johns, a silversmith and technical tutor at Middlesex Polytechnic (as the University was then) received a phone call from a French company called Metaleurop SA. Metaleurop’s primary business was the mining and refining of lead and zinc. As a by-product of this activity many other metals are also recovered, including a little known metalloid called germanium.

Germanium was first isolated in 1886 but no commercial use could be found for it until World War II when it was used for the development of radar. After World War II the first transistors were made using germanium and it is still used in high-speed electronic devices. The reason for Metaleurop’s phone call to Peter Johns was the ending of the Cold War and “the peace divided” reducing the demand for germanium. The largest use at that time for germanium was in night vision systems used for nearly every fighting vehicle. Metaleurop wished to research possible new uses for germanium in the jewellery industry.

Initially the company asked Johns to test a copper germanium alloy to see if it would be satisfactory for jewellery. He found it perfectly workable and a very good alloy for casting. However he could not see a big future for a high copper alloy in the traditional jewellery market. A question by one of his students about firestain started Johns thinking about using germanium to eliminate the problem from sterling silver.

Patent applied for

Metaleurop found his idea interesting and funded a one-year study though Middlesex Polytechnic. The long-term plan was that when the initial research was finished, bullion manufacturers would take over and complete the development of the alloy. Unfortunately changes in market conditions and an unforeseen problem with its zinc refining plant caused Metaleurop to cut back its production of germanium and cancel its research plans. At this point Johns took over the project and completed the development. A UK patent was granted with Peter Johns named as inventor in 1996, seven years after the first phone call.

Initially the research was directed towards a binary alloy of silver and germanium. Although the result was an alloy with good tarnish resistance, it was far too soft. In the next experiments small amounts of copper were added to try and increase hardness. No firestain was seen with the addition of the copper. More copper was then added and the amount of germanium reduced until the optimum levels were determined. During the research process it was discovered that the new alloy had some interesting hardening properties - simply baking it in an oven could make it harder than normal sterling silver. The low heat hardening process was accessible to all as it was possible even in a normal kitchen oven. As part of a jointly funded European project the welding properties of the alloy were investigated. The Sheffield-based Cutlery and Allied Trades Association carried out tarnish tests to ISO standards.

Into production

Production of the new alloy first commenced with a company in Finland called, Kultakeskus OY. A sudden rush of publicity on Finish television and in newspapers resulted in a need to name the new alloy and it was quickly christened “Super Silver”. Production in Finland attracted the attention of an American entrepreneur who with some bravado established interest from Tiffany & Co.

Initially Tiffany was supplied from Finland. However interest in the new alloy was also being driven by publicity on Internet forums and the newly established medium of blogging. In the summer of 2003 Johns went to the America with a mission find a manufacturer. In early 2004 an exclusive manufacturing contract was signed between Middlesex University and Stern Leach, the largest precious metal alloys manufacturer in the US.

A new company

By 2004 the University had established a spin out company under the management of its own commercial division. Professional marketing support was also recruited from within the University. A strategy was developed to establish Argentium as the first ‘endorsement’ brand in the field of jewellery alloys. A new name was also registered world wide, ‘Argentium Silver’. In 2004 Argentium Silver won the first AJM award for innovation at the New York Expo. It is given for products “that are making a difference now and will in the future”.

From 2004 – 2008 Argentium Silver consolidated its marketing position and established a reputation as the premier sterling silver alloy in the US market. Production reached over three million troy ounces annually. In 2008 Argentium Silver was sold by Middlesex University to private investors. The new company is named Argentium International Ltd. The company statement reads

Argentium International are dedicated to establishing Argentium as the global leader and industry standard for premier silver – ideal for those who value quality and wish to rise above the crowded commodity driven jewellery and silverware market.

Conferences and presentations

Peter Johns has been invited to several key, internationally renowned jewellery and silverware manufacturing conferences as a keynote speaker. This demonstrates his standing in the field and the curiosity and seriousness with which his work if viewed. His first such invitation was to the Santa Fe Symposium in 1997. This is considered to be an accolade to his work and is viewed by his peer groups as an honour. As well as having been an invited speaker, he has also contributed papers to refereed conferences.

Argentium Silver is a growing subject of discussion, providing interesting topics for scientific and practical silversmithing subjects. This list includes key speakers who are experts in these different fields.

2007 Presentation/discussion by Ronda Coryell – comparing the various processes of granulation, at Clasp 2007 Conference 'Dinner with the experts'. Title: "Argentium & Working With Different Metals", held Denver, Colorado, 14-16 September 2007.

2007 Joint paper by Peter Johns and Sam Davis “The Properties and Applications of Argentium® Sterling Silver”, presented by Sam Davis at the 31st IPMI (International Precious Metals Institute) Conference, Doral Golf Resort and Spa, Miami, Florida, 9-12 June 2007. Proceedings published by the International Precious Metals Institute.

2007 Presentation “Argentium Sterling Silver: Past, Present and Future”, given by Peter Johns and Sam Davis at MIT (Massachusetts Institute of Technology), Cambridge, MA, 25 January 2007.

2006 Joint paper by Kristina Niedderer, Peter Johns and Clare Harrison “Exploring the Creative Possibilities of Argentium™ Sterling Silver”, presented by Kristina Niedderer at ‘Wonderground 2006’ Design Research Society International Conference in Lisbon, Portugal, 1-4 November 2006. Proceedings published.

2003 Presentation “Argentium® Silver” given by Peter Johns at the Society of American Silversmiths annual conference ‘SilverWorksV’, held in Providence, RI, USA, 23 August 2003.

2001 Peter Johns - invited speaker at the ‘Institute of Materials’ Conference ‘Precious Metal Fabrication in The Jewellery Industry II’, held at the School of Jewellery, University of Central England, Birmingham, 4 July 2001. Title: “Tarnish Resistant Silver”.

2000 Peter Johns - invited speaker at the 'Association for Contemporary Jewellery Conference - A Sense of Wonder' held at the International Conference Centre, Birmingham, July 2000. Title: "Silver/Germanium Alloys". Proceedings to be published 2001.

1998 Peter Johns - invited speaker at Central Saint Martins College of Art and Design. Title: "Development of a New Silver Alloy and Modern Production Techniques".

1998 Peter Johns - invited speaker at 'Silver Symposium 1998', held at the University of Central England, Birmingham. Title: "Firestain Resistant Silver Alloys". Event sponsored by the Crafts Council.

1998 Bernie Wire at ‘The Santa Fe Symposium on Jewellery Manufacturing Technology 1998', Albuquerque, New Mexico, USA, held 17-20 May. Title: “Weldable Silver Alloy". Proceedings published by Met-Chem Research Inc. ISBN 0-931913-27-6, Pg. 337-362.

1997 Peter Johns - invited speaker at 'The Santa Fe Symposium on Jewellery Manufacturing Technology 1997', in Albuquerque, New Mexico, USA, 18-21 May. Title: "Fire Stain Resistant Silver Alloys". Proceedings published by Met-Chem Research Inc. ISBN 0-931913-25-X, paper cited Pg. 33-67.


The following are Peter Johns’ UK/European patents, each one representing a separate invention. Some UK patents will also be granted in Europe and vice versa. The date is the year of grant.

Many of these patents are also filed in other territories world wide.

1994 GB 2255348 Novel Silver-Copper-Germanium alloy

1996 GB 2283933 A method of joining materials together by a diffusion process using silver/germanium alloys.

1996 GB 2283934 A method of joining materials together by a diffusion process and a silver/germanium alloy for use in the method.

2005 GB 2402399 A Silver-Germanium-Copper Alloy

2006 GB 2408269 Silver Solder or Brazing Alloy and their Use

2008 GB 2414739 Process for making Finished or Semi-Finished Articles of Silver Alloy

2008 GB 2412666 Water Based Metal Treatment Composition

2008 EP 1699581 Silver Chain Manufacture

2008 EP 1794335 Method of Producing a Copper-Germanium-Boron Master Alloy and its use in making Silver-Copper Alloys.

Peter’s research outputs in the Middlesex Repository