If you have a question concerning the industrial uses of gold or perhaps need some technical information to assist in an application, contact us using the form provided.

You can read answers to a selection of previous questions below:

Can gold be used in thermocouples?

Gold has found use both for low temperature and higher temperature measurements. An alloy based on small additions of iron to gold displays a strong and reproducible thermoelectric effect and as a result it has found use for cryogenic temperature measurement near absolute zero. Gold-cobalt alloys have also been used in the past, but such alloys have exhibited larger drift. At higher temperatures, use of gold-palladium alloys have been described, for example in aircraft engines where good service lives at elevated temperatures are required.

In what sort of applications might gold catalysts be used in the future?

Gold had been overlooked by most researchers as a possible industrial catalyst until very recently. However, there is now a growing excitement about the potential gold may hold for catalysing industrial reactions. The following reactions have now been shown to be effectively catalysed by supported gold catalysts:

• Carbon monoxide oxidation, including selective oxidation in a hydrogen stream
• Catalytic combustion of hydrocarbons
• Hydrochlorination of ethyne
• Hydrogen + oxygen reaction to give hydrogen peroxide
• Hydrogen sulphide and sulfur dioxide removal
• Oxidation of glucose to gluconic acid
• Oxidative decomposition of dioxins
• Oxidative removal of mercury
• Ozone decomposition
• Reduction of NOx with propene, carbon monoxide or hydrogen
• Selective oxidation, e.g. epoxidation of olefins,
• Selective hydrogenation, e.g. of alkynes and dienes to mono-olefins
• Vinyl acetate synthesis from ethene, acetic acid and oxygen
• Water gas shift

One of the most exciting things about catalysis by gold are the 'light off' temperatures that are achieved (that is the temperature at which the catalyst becomes functional). Potentially, gold catalysts operate best in the temperature range 200-350K, compared say, to a platinum catalyst's optimum performance in the range 400-800K. Unlike many other platinum group metal catalysts, the presence of a high humidity is actually beneficial rather than detrimental to the activity. It is unlikely that gold will largely replace platinum group metals from their dominant position in precious metal catalysts. More likely is the potential to catalyse new reactions and in some cases offer alternative cost effective solutions. For more information see www.goldcatalysis.org

I work in the precious metal industry. Where can I get new technical information about gold?

For up to date technical information, we would recommend the technical journal Gold Bulletin www.goldbulletin.org which is published every quarter (by World Gold Council) and contains newly published research papers related to gold. It includes papers on the latest research advances, state-of-the-art reviews, conference reports, book reviews and highlights of patents and scientific literature. The journal is read by chemists, physicists, engineers, metallurgists, materials scientists, biotechnologists, surface scientists, and nanotechnologists amongst others, both within industry and academia.

I am interested in screen printable gold pastes or liquid gold etc for decoration work on ceramic tiles and pots – what is this product and where can I source it from?

Liquid gold is also known as bright gold and is widely used in the decoration of ceramics and glass. Liquid gold was first manufactured by the technical manager of the Royal Porcelain Factory at Meissen in Saxony in the early 1830s but the formula for mixing gold powder in suspension with natural oils and chemicals was kept secret until 1851 when a patent was taken out. Degussa, the German precious metals group, started liquid gold production in 1879 and shortly afterwards shared its knowledge with Johnson Matthey in Britain. From 1905 Engelhard Industries, Hanova liquid gold division, became the main supplier for the American market. Look in the decorative section of UtiliseGold for contact details and website addresses.

Liquid gold may be applied to ceramics and glass by manually brushing, screen printing or spraying. The object is then heated in air to burn off the organic components, leaving behind a thin bright film of gold.

Alternatively a rich, matt gold finish may be required and in this case a burnish gold formulation is used. This contains gold flake and/or powder and is fired to a dull matt film which is then hand burnished to the final rich gold appearance.

What is gold bonding wire, I’ve heard it mentioned in relation to the electronics industry but am not really sure what it is?

One of gold´s main uses in the electronic industry is in the form of extremely fine wires used to connect parts of semi-conductors such as transistors and integrated circuits. Gold is used to ensure reliable connections between components. This gold bonding wire is specially refined to high purity (999.99% gold) and would typically be thinner than a human hair (10-200microns). Billions of gold bonding wire joints are bonded every year in the world, mainly for the numerous integrated circuits (ICs) produced.

What are the magnetic properties of gold?

Although gold itself is essentially non-magnetic, gold alloys high in iron, cobalt and nickel are strongly ferromagnetic and some of these have found industrial applications. The effectiveness of additions of gold to Permalloy in substantially reducing the switching time in Permalloy type magnetic cores has been recorded. Au-Co-Fe alloys have found application in telephone switching systems. Au-Fe-Pt alloys have found use as permanent magnets.

I have heard that gold compounds are used in the treatment of arthritis. Is this true?

Gold and gold compounds have historically been used in drugs for the treatment of a wide range of ailments. This use of gold compounds in medicine is called chrysotherapy. The Frenchman Jacques Forestier reported in 1929 that the use of gold complexes was beneficial in the treatment of arthritis. Later work after the Second World War demonstrated conclusively that gold drugs are effective in treating rheumatoid arthritis patients. Two of the most commonly referred to gold compounds in such treatments are Myocrisin and Auranofin