Emma Oliver, Morgan Allington, Antena Solomon and Andrada Dumitrascu, of Balclutha Primary School asks :-

Who first found gold, which countries does it come from, and can scientists trace it back to a particular mine?

Paul Craddock, a metallurgist at the British Museum, responded.

Gold occurs as shiny metal nuggets in many places all over the world. So one might think that man would have been interested in it from the very beginning, but this seems not to be so. The first metal to be used was native copper about 10,000 years ago in the Middle East. Similarly the indigenous inhabitants of North America used native copper but not gold (and I don't think the Maori ever used gold in New Zealand did they?).

So the first use we know about were some stone age farmers who lived near what is now Varna in Bulgaria about 7000 years ago and the bodies in their cemeteries were adorned with hundreds of pieces of sheet gold. Thereafter gold seems to have become appreciated rapidly around the world.

Most elements are present in varying amounts all over the world and the same is true of gold. As gold is very valuable people have found it worth while to pan it from rivers and mine from very many places. There were the famous gold rushes to California and Western Australia (and even New Zealand) and the Klondike in the 19th century. The Kolar mines of South India were reopened after 2000 years and became very important in the early 20th century. Later on the South African mines were developed and continues to be the World's major source although Russia and now some of the states in Central Asia are also important suppliers.

Can scientists tell where it can from? Well yes up to a degree. If the places from where it could have come from are known and if there are not too many of them it is possible. In Australia they have a major problem with theft at the gold mines. Quite a lot of the gold literally walks out of the mines in the miner's pockets. When this gold is offered for sale to a bank it is great help in catching the thief if the police can prove that it came from a particular mine. So the gold from each of the main gold mines in Australia has been analysed by a very sensitive analytical technique with the wonderful title of Laser-ablated Inductively Coupled Plasma Mass Spectrometry. That can detect elements in the gold down to parts per billion (0.000,000,01 per cent) and produce an analytical fingerprint for the gold from each mine. Thus when suspect gold is offered for sale at least they can tell where it came from originally.

The Natural History Museum in London have produced a rather good little booklet entitled 'Gold' (Herrington, Stanley and Symes) on gold intended for general interest, covering many aspects of its mineralogy, mining, history and many uses.