What is silver?
Silver is a ductile, malleable, brilliant greyish-white metal.

The chemical symbol for silver is Ag, meaning 'argentum' - an ancient or poetic word for silver. The term 'sterling' for English currency denotes a specific weight of silver. When we say something is 'sterling' we mean 'excellent'.

The price of silver and other precious metals is quoted in terms of troy ounces. The term 'troy' is derived from Troyes, France, a major trading city of the Middle Ages. One troy ounce equals 31.1 grams.

What are the properties of silver?
Silver has the highest electrical and thermal conductivity of any metal. It is malleable (easily shaped), ductile (can be drawn into very thin wire) and has antiseptic properties.

Where is silver found?
Silver is found as a free metal in nature or bound up with rock and too small to see with the naked eye. It is often, but not always, found in association with gold or other metals. Martha Mine is the only current producer of silver in New Zealand. The metal particles are mixed with the rock and too small to be seen. 85% of the precious metal produced at Martha Mine is silver.

What has silver been used for in the past?
Silver has had many practical and artistic uses. Because it was found as a free metal and was easy to work it was put to a variety of uses. The early discovery that water, wine, milk and vinegar stayed pure longer in silver vessels, led to its use as a container for long voyages on land and sea over 2,500 years ago.

What is silver used for today?
The many properties of silver mean that it is widely used today in science and technology. Each year over 7,000 new patents and papers are published which describe a product or process in which silver is a vital part.

Silver has a range of specialised electrical, mechanical, optical and medicinal properties. Silver is used in solar panels and spacecraft, plumbing and pendants. It has not been an easy metal to replace as new technology reveals additional applications.

Technology
The photographic industry takes 35% of the silver used each year throughout the world. Silver halides, coupled with dyes produce colour photographic images. X-Ray and black & white photography also rely on silver.

Watches, cameras and calculators use silver in their batteries to provide higher voltage and longer life. Silver oxide-zinc batteries, which have twice the electrical capacity of lead-acid batteries of the same size, are used extensively in aircraft and submarines, where weight is critical.

Silver concentrates the sun’s rays on solar collectors, It is found on the backs of mirrors and protects the heat-reflecting gold film on windows. Under the keys of almost every personal computer is a panel of switches with silver contacts to carry out the countless millions of instructions.

Silver thiosulphate prevents the release of ethylene gas from cut flowers to produce longer lasting blooms destined for export. Silver can be prepared as crystals of silver iodine and seeded into cold cloud to produce raindrops or snowflakes.

Microwave cooking is made more appetising due to a silver alloy coating applied to the bottom of microwave cookware. The surface of the cookware will reach 260 degrees C in five minutes, resulting in a browning or crisping of food surfaces.

We use the term 'silverware' to indicate the best cutlery. Many of the best table accessories such as knives, forks and spoons; jugs, serving dishes and trays are made out of silver.

Burns are disinfected with silver creams and bones are mended with cement containing antibacterial silver salts. Silver is combined with the powerful chemotherapeutic agent sulphadiazine to produce a drug 50 times more powerful than sulphadiazine alone. It is the most widely used drug for treating burn wounds.

Silver is also widely used in dentistry. Silver nitrate can be administered to new-born infants’ eyes to eliminate the incidence of Gonococcal Ophthalmia, a disease which can cause blindness.

Key Words & Concepts

• Silver is more plentiful than gold, but still a rare metal. Its chemical symbol is Ag.
• Silver shares many of the same properties as gold.
• Like gold, silver is malleable (easily shaped) and ductile (easily stretched into thin wire).
• Silver is the best conductor of electricity and also the best thermal conductor.
• Silver has been used for thousands of years. Today new technologies find many new uses.

Links to other sections of the Martha Mine website
To find out how the precious metal is detected in rock see Assay Procedures.

To find out how gold is separated from rock and processed see Mining @ Martha

What happens to gold and silver after it leaves Martha Mine?

For information about Martha Mine and the environment see Rehabilitation

Links to other websites
These links will take you outside the Martha Mine website and open in a new window. Close the window to return to this site.

Silver Institute www.silverinstitute.org

For further information on historic gold and silver mining in the Waihi area, see the Waihi Gold Mining Museum and Arts Centre site waihimuseum.co.nz

Waihi isn't the only historic gold mining area in the Coromandel. For information about resources and activities based around the historic Thames goldfields see www.thames-info.co.nz/GoldfieldPromotions/

For more information about minerals and mining in New Zealand see the New Zealand Minerals Industry Association site at minerals.co.nz
This site features a major section on gold and silver written specifically for school students and also includes a wide range of associated information and educational resources for schools.

Waihi Gold Company is planning to construct an underground mine on mainly company-owned farmland outside Waihi. For more information about how an underground mine is planned, permitted and constructed see www.favona.co.nz