Gold, has always been considered one of the most precious and lustrous of metals and has held its allure since its early days. The first gold artefacts come from a few small towns in what is now Bulgaria, central Europe. These treasures have been wrought by humans, evidence of a thriving gold mining and metallurgical prowess roughly 6000 to 7000 years ago.
How to find gold
Geological conditions which are conducive to the formation of gold may differ from one deposit to another. There are however, certain common elements which are associated with the majority of global gold deposits. So, if you’re looking to find a new gold deposit, remember:
- Gold is frequently associated with the presence of quartz rock, in alluvial deposits appearing as pebbles in riverbeds or reefs in hard rock as well as epithermal and porphyry veins
- White-coloured quartz may be found as small stones in river beds or in reefs found in large seams in hillsides and underground
- Gold can present as a vein in the quartz. Studies indicate that gold veins within the quartz, are deposited when high-pressure and temperature geothermal water in which the gold is dissolved, is disseminated through a host rock and crystalisation occurs as it cools.
How gold is mined
Gold may be mined from open pits, and shallow and deep underground mines, depending on the local geological and ground conditions.
With increasing modernisation in the gold industry, the focus on mechanised mining methods has increased in many mines worldwide. In South Africa, it is a particular area of focus, both in order to engineer out hazards and safety concerns, but also in an important drive to maintain the mines’ profitability.
USES OF GOLD
Gold’s appeal as an adornment has persisted over time and it retains a significant roles in the jewellery industry. The metal is malleable and resistant to corrosion and tarnishing and lends itself to being wrought into fine pieces, which withstand ageing. By alloying gold with other metals, it is possible to create white, yellow and rose gold pieces of jewellery:
Yellow is the traditional colour for gold jewellery, and is at its most pure at 24 carats; 18 carat gold contains 75% gold, with the balance comprising other metals eg. copper or silver; while 9 carat is the lowest caratage permissible in most parts of the world.
Metals such as nickel, silver and palladium are added to gold in order to create white gold. These other metals lend strength and durability to the jewellery pieces.
Rose gold is made of gold mixed with copper and silver alloys. Copper contributes the reddish shade to the gold, and silver adds strength.
In the world of finance and markets, The London Bullion Market Association (LBMA) has certain specifications for their Good Delivery List, which provides comfort in terms of the purity and provenance of gold metal worldwide. Global member refineries are required to comply with the LBMA in order to be accepted on the prestigious Good Delivery List. Good delivery gold bars weigh approximately 400 troy ounces – or 12.5kgs (one troy ounce is approximately 31.1 grams).
Physical gold may be bought as an investment in the form of gold bullion,bars or coins. Other ways to invest indirectly in gold arethrough shares in gold companies; unit trusts or mutual funds; ETFs and other similar investment funds and instruments.
For years, until 1971, many countries’ currency values were linked to a specified amount of gold. This was known as The Gold Standard. As each currency was fixed in terms of gold, exchange rates between participating currencies were also fixed. After World War 2 a new international system, known as the Bretton Woods system was put in place to provide both stability and flexibility. Nevertheless, gold’s value remains in place, and it is still considered to be a safe haven in times of uncertainty and fear.
New uses of gold
In the modern era, gold’s properties have been innovatively applied in a number of technological, industrial and medical applications. Gold is used in catalytic converters and in space travel gold to protect against radiation and heat. In the medical field gold nanoparticles have become commonplace in rapid diagnostic testings, thereby transforming disease diagnosis over the past decade; at the same time scientists at the Imperial College London are working on early detection of the HIV virus, using experimental gold nanoparticle techniques, a project being supported by the World Gold Council.
Discoveries around gold’s ability to reflect infrared light resulted in microscopically thin gold coatings being used in NASA’s James Webb Space Telescope, due to be launched in 2021, which will search for the first galaxies formed in the early universe. Similar coatings are also used by engineers to reflect heat radiation, thereby assisting temperature control in buildings, lowering their energy costs and reducing carbon emissions.
Also in the field of environmental health, gold nanoparticles are being used to improve the efficiency of solar cells, and research into the use of gold-based materials in the search for new, more effective fuel cell catalysts has pointed to further positive applications for this precious metal.