Submitting Institution
Middlesex UniversityUnit of Assessment
Art and Design: History, Practice and TheorySummary Impact Type
TechnologicalResearch Subject Area(s)
Engineering: Materials Engineering
Summary of the impact
Argentium, a sterling silver alloy with unique properties, has stimulated
jewellers to develop designs retailing in over 1,220 high street shops in
the UK alone and craft jewellery makers to extend their design practice
around the world. A spin-out company from Middlesex was sold to private
investors in 2008. Middlesex remains in partnership with Argentium
International Ltd., and retains a board seat. The seven companies
presently licensed to manufacture Argentium alloy are Legor Group,
Heraeus, GSM Metals Inc, Lamet Spa, Noble Mind, Nubia and Pasavento. Route
to impact was creation and protection of intellectual property, and its
exploitation through a spinout company. Beneficiaries include
silversmithing and craft industries, jewellery retailers, and users of
Argentium Silver.
Underpinning research
Research at Middlesex showed that germanium possessed many properties in
alloy with silver: firescale elimination; high tarnish resistance;
precipitation hardening and simple heat- hardening properties; increased
ductility; increased thermal and electrical resistance (making alloys
suitable for welding and laser forming); and environmental advantages
(associated with not having to remove, or plate over, firescale).
Argentium complies with safety standard ISO 8442-7, allowing it to be used
in food utensils. Other claims have been proved by subsequent research
such as the following valuable characteristics for jewellery craft
workers:
- Easier soldering/brazing due to the suppression of the copper oxide.
- Can be fusion and resistance welded.
- Cost savings on finishing, so there is no need to strip or plate over
firestain.
- Environmental, health, and safety advantages, with no need for plating
and hazardous cyanide or other stripping chemicals.
- Precipitation hardenable by heating at temperatures obtainable in a
domestic oven.
- Superior ductility.
- Higher tensile strength.
(see http://www.silversmithing.com/1argentium.htm)
[Accessed 14/11/13]
Underlying research was undertaken at Middlesex by Peter Johns
(1971-2004) - this specific research being funded by a CRAFT/BRITE-EuRam
grant (BRE20289 - BE 5721) of €200k to a TNO-led consortium including
Middlesex. Research on Argentium led to grants of patent to the
University. The first silver/germanium alloy patent, `Novel Silver-based
Ternary Alloy', was granted in 1994 (GB 2255348). The key breakthrough for
the team's research came trough investigations on joining and bonding,
specifically USA Patent No. 6,168,071 in 2001. Subsequent patents extended
claims in relation to germanium silver alloy. Johns has remained a
lecturer at Middlesex since 2007 while simultaneously holding the position
of Research and Development Director at Argentium International Ltd. Johns
was the first recipient of the Manufacturing Jewellers Society of America
Innovation Award for his work on Argentium.
Research has focused on the changed conditions for working silver by
silversmiths. Argentium sterling silver replaces some of the copper in the
silver alloy with germanium which has the benefit of eradicating silver
tarnishing (due to a reaction with sulphurous gases in the atmosphere) and
firestain (reddish-purple oxidation on the surface of sterling silver when
heated in the presence of oxygen). Both tarnish and firestain impose
limitations on silversmith design and fabrication.
Experience with Argentium has suggested new techniques and processes in
silvermithing, allowing new applications and designs in the jewellery
industry, and research continues to develop applications and manufacturing
methods. For example, a joint research project with Wolverhampton
University and industrial partners is being undertaken to develop direct
laser sintering of Argentium Silver alloys. A collaborative project is
also being undertaken with a US company, The Bell Group, to produce a
precious metal clay for the jewellery craft market and a new technique for
investment casting (patent GB2485374 filed 11th November 2010)
is in development by the company.
Accessible introductions to Argentium are provided by videos produced by
users, the inventor and the company:
http://www.youtube.com/watch?v=LcVMTeqpAs4
(Peter Johns)
http://www.youtube.com/watch?v=RcR_oj5yFgE
(Ronda Coryall)
http://www.youtube.com/watch?v=RQ8N5Yopam0
(Argentium Silver)
References to the research
1) Johns, P.G. (2001) [patent], A method of joining metals
together by a diffusion process using silver/germanium alloys. USA Patent
No. 6,168,071 - granted 2/1/2001. Patents are granted only after a
rigorous, open, international review by industry and peer organisations,
and are required to demonstrate novelty, `non-obviousness' and
application. Scrutiny includes detailed examination by professional patent
examiners at national patent offices, which includes a search of `prior
art' (research) to establish the novelty and value of the contribution
made by the patent. See also references 2, 3, 5.
2) Johns, P.G. (2013) [patent], Alloy for investment casting. (UK
Publication Number GB 2485374, granted 25/06/2013. Currently under
examination in the US).
3) Johns, P.G. (2004) [patent], Process for making finished or
semi-finished articles of silver alloy comprising copper and germanium.
(UK Application No. 04 12256.0 filed 2/6/2004, & UK Application No. 04
21172.8 filed 23/9/2004).
4) Harrison, C., Johns, P.G., Niedderer, K. (2006) [conference
contribution] `Exploring the creative possibilities of Argentium (TM)
Sterling Silver'. In: Proceedings of Design Research Society
Conference Wonderground. IADE: Lisbon. Design Research Society. This
conference publication is of international standing and the quality of
papers was established through peer panel review.
5) Johns, P.G. (2006) [patent], Silver solders or brazing alloys
and their use. UK Patent No. GB2408269 - granted 22/2/2006.
6) Johns, P.G., (1997) [conference contribution] 'Fire Stain Resistant
Silver Alloys'. The Santa Fe Symposium on Jewellery Manufacturing
Technology, Albuquerque, New Mexico, USA, 18-21 May. Proceedings
published by Met-Chem Research Inc. ISBN 0-931913-25-X, paper cited pp.
33-67.
Details of the impact
The Argentium Silver project team was led by Johns as a research project
in metallurgy with specific applications in craft jewellery. The research
has led to widespread use of Argentium, particularly in the jewellery
industry.
(i) Routes to impact
The research resulted in international patent filings, trade-paper and
authoritative trade journal citations, trade fair exhibitions,
demonstrations and presentations, press coverage, academic papers,
adoption of the material by significant practitioners, and business growth
of a company. Of the 16 patents granted and pending in Europe, USA and
further internationally, it is those connected with the joining and
bonding of germanium/silver alloys that have allowed the material to be
developed commercially and in craft silversmithing.
The ability to diffusion bond and weld Argentium Silver opens new avenues
for the design and production of silverware and jewellery. For example,
United States Patent 6,168,071 (granted 2001) protects the intellectual
property covering diffusion bonding as a method of joining metals together
without the addition of a solder or `filler' welding material.
Craftspersons using traditional jewellery equipment can easily perform
this process with Argentium Silver.
(ii) Impact on the industry and on practice
Total tonnage of the new alloy shipped is a difficult figure to assess but
we estimate about 40 tonnes of Argentium are currently being sold
annually. Whilst that is still a small proportion of the total silver
fabrication for jewellery and silverware globally (currently c.7000 tons
per annum) this represents a significant contribution to the specialist
market for a unique silver alloy. The most important market for Argentium
Silver is the USA (c.3000 jewellers). Argentium is used by a wide range of
US brands including Tiffany & Co, David Yurman, JC Penney, Home
Shopping Channel, Walmart, Novell, Signet Group, and Eternal Jewellery.
Three of the high street retail outlets from which one can buy Argentium
Silver jewellery in the UK during the reporting period are: H. Samuel with
304 stores, Ernest Jones with 180 stores, and Argos with 740 stores. Major
brands, such as Kit Heath, have now committed themselves to providing
Argentium products for British consumers, after `Responding to retailer
feedback both in the UK and the USA, ...in order to combat the tarnishing
of traditional sterling silver. This is a first for an established high
street brand here in the UK and across the world. This is great news for
our retailers and our consumers - for a brand already renowned for
exceptional quality, the introduction of Argentium creates a truly
outstanding offering for the UK market.'
(http://masterjewellers.co.uk/news/404/kit-heath-and-argentium-achieve-world-first/
)
However it is not through volume sales of Argentium alone that the
research has made an impact on jewellery making and the jewellery
industry. The Argentium Silver Guild
(http://www.argentiumguild.com )
was set up in January 2011 to unite a worldwide community of Argentium
silversmiths and artisans. It provides a place for Argentium users to
share their knowledge and experiences and to foster excellence through
good practice and inspiration, and a number of Guild members and others
have reported on the extent to which Argentium has enabled new practice in
jewellery making. Some 49 contemporary silversmiths using Argentium, and
members of the Guild, show their work at
http://www.argentiumsilver.com/#!__gallery, demonstrating the range
of impact on silver fabrication practice - including use of Argentium by
instrument maker Landell Flutes, the adoption of Argentium in the
skeuomorphic bowls of Lucian Taylor and the innovative designs of David
Worcester Jewellery.
Samara James, a leading producer of high quality jewellery, notes that
`What this new trend in using this alloy for wedding and engagement rings
has done is to open the doors to more research being done in the field of
silver alloys so that the metal can be much better for both the jeweller
to work on and the customer to wear'
(http://www.samarajames.com/blog/2008/11/19/argentium-silver-better-for-engagement-and-
wedding-rings [entry posted on Wednesday, November 19th, 2008 at
4:53 am, filed under `Jewellery News']. Indeed The Evening Standard
Newspaper described Argentium in their 'Design trends - silver'
article published on 28th September 2011 as `the new magic
stuff used by many new makers' precisely because of the new possibilities
discovered by craft makers. G&S Metals, one of the largest silver
jewellery retailers, notes that `Fabrication and workability
characteristics are much better than standard Sterling silver, and it can
be heat treated to achieve hardness approximately twice as strong as
standard Sterling Silver...Argentium Silver is excellent for making
durable, tarnish resistant silver products' (http://www.gsgold.com/catalogs/Argentium-May2011.pdf
). In short, designers and makers in both atelier craft manufacture and
jewellery retailing are readily exploiting the benefits of Argentium in
their work.
Sources to corroborate the impact
- Argentium.com website and resources: http://www.argentiumsilver.com/#!__technical-
resources/vstc1=silversmiths-and-artisans [Accessed 14/11/13].
Argentium gallery at:
http://www.argentiumsilver.com/#!__gallery
[accessed 15 May 2013].
- Charles Allenden, `The Argentium Revolution', 23rd June 2012, The
Studio, Rio Grande's Blog, http://riograndeblog.com/2012/07/the-argentium-revolution/
[Accessed 14/11/13]
- `Your Argentium - Interview with Cynthia Eid', Argentium Guild
Newsletter, Issue 2, January 2012 (for evidence of craft working
benefits of Argentium). The pdf document is available at: http://www.argentiumguild.com/#!__newsletters
[Accessed 14/11/13].
- Eid, C. (2006). `Road Testing Argentium Sterling'. Art Jewelry, 2(6)
(for evidence of craft working benefits of Argentium). The pdf document
is available at:
http://www.cynthiaeid.com/images/pdfs/ArtJewlry-RoadTest.pdf
[Accessed 14/11/13].
- Ronda Coryell, twenty videos on the use of Argentium in silver
jewellery making.
http://www.youtube.com/user/rondacoryell/videos
Total number of views: 57.843 views [Accessed 14/11/13].
- `Argentium Sterling', by Jeffrey Herman, article for the American
Society of Silversmithing, ShopTalk section of the official website http://www.silversmithing.com/shoptalk.htm
direct link is: http://www.silversmithing.com/1argentium.htm
—silver smith and educator. [Accessed 14/11/13].
- Allied Gold, official distributor for Argentium in the UK
www.alliedgoldltd.com (for evidence of the wholesale reach of
Argentium). [Accessed 14/11/13]