In 2014 the Australian Centre for Ancient Numismatic Studies at Macquarie University teamed up with the Bragg Institute to try to solve a 2500 year old mystery. Shortly after the invention of money in Lydia in the late 7th century BC a number of Greek colonies began a unique coin minting method known as incuse coinage. In existence from around 600 BC in the cities of Southern Italy (modern Basilicata and Calabria), incuse coins were known for the image on the front of the coin also appearing on the back, but in reverse. The incuse coins are much thinner and much more precisely aligned and struck than contemporary Greek coins. With their abrupt disappearance after 150 years, little is known today about the minting technique used to produce these rare coins, though various theories have been proposed over the last century. Using the Neutron Beam instrument Kowari for Neutron Texture analysis, and Dingo for Neutron Tomography a series of 27 incuse and non-incuse coins has been studied over the last 12 months with the aim of understating the manufacturing process. Neutron Texture analysis of coinage from different Greek colonies indicates the incuse coins were made using a similar process and this process was significantly different to the standard coinage made on the Greek mainland at the same time. Neutron Tomography also indicates this. Tomography allows scientists to have a unique insight into the internal structure of a coin and has generated details on porosity and inclusions which cannot be obtained elsewhere. The most startling find is that a number of ancient coins believed to be pure silver are infact, mostly copper with a thin layer (0.4mm) of silver over the top. Tomography allows precise measurements of the thickness of the outer and inner layers and gives an idea as to their method of production.
|Number of pages||1|
|Publication status||Published - 2015|
|Event||Asia Oceania conference on neutron scattering (2nd : 2015) - Sydney, NSW|
Duration: 19 Jul 2015 → 23 Jul 2015
|Conference||Asia Oceania conference on neutron scattering (2nd : 2015)|
|Period||19/07/15 → 23/07/15|