Dr Ross Ramsay
Publish Date: Friday, 1 May 2020
Dr Ross Ramsay

Environmental Management tutor

Ross holds a Bachelor of Science and Master of Science (Hons) degrees from the University of Auckland and a PhD in Earth Science from the University of New England. He teaches on the Environmental Management degree programme. He has headed a collaborative research project with Dr Chris Adams (Geological and Nuclear Sciences) and Mr Russell Beck into radiometric dating of detrital zircons contained within the quartzose metasediments of the Pegasus Group, Rakiura (Stewart Island), New Zealand.

These rafts of metasediments ranging from quartz-rich to partially calcareous rocks are found included within a spectrum of later granites. As Ross explains: ‘traditionally these metasediments  have been dated to around four hundred million years old, however our research is revealing that the some contained zircons are actually much older than that – some dating to 3 billion years +.’

Zircon is a zirconium silicate mineral (ZrSiO4) that belongs to the tetragonal crystal system and has an SG of 4.7.  ‘Zircon has the ability to take in and incorporate crystallise small amounts of the unstable element uranium,’ says Ross.  One isotope of uranium is 238U which decays with a half-life of 4.47 billion years to 206Pb (lead).  Another isotope of uranium, 235U decays to 207Pb with a halflife of 704 million years (0.704 billion years).  ‘We know the rate at which these isotopes decay so we can use that information to find out when the detrital zircons within the Pegasus Group metasedients on Rakiura crystallised.’

In January 2014 Ross, Russell Beck, and Dr Adams collected representative samples from Table Hill, Blaikies Hill, and Mt Allen on Rakiura.  ‘Our sample sites were very remote,’ says Ross.  ‘We were lucky to have help from Helisouth who provided helicopter access to the high mountain areas.’  Representative quartz-rich samples were collected and crushed, and those that contained heavy minerals including zircon were separated.  The researchers found that, as sampling progressed south from Table Hill, the sediments based on texture appeared to increase in the grade of metamorphism.

Using the GEMOC facilities at Macquarie University, Dr Chris Adams was able to analyse and date 56 detrital zircon mineral grains from a sample collected from Table Hill.  Preliminary analysis of the age data reveals a curious history.  ‘The analysis indicates that some zircons, derived from very old sialic crust that is no longer recognised in or adjacent to New Zealand, have been shed into sediments that were reworked and finally incorporated into the Pegasus Group metasediments of Rakiura,’ Ross explains. ‘This dates the age of the host sediments (Pegasus Group) which we know to be no older than about 350 million years.’

In addition to his geological studies Ross has also continued his ongoing forensic science research into mid18th century English magnesian porcelains.  To date published research by Ross has established that three recipe types were used at Lund’s Bristol porcelain works (1749-1752), namely a porcellaneous stoneware (Si-Al), a soapstone - lead body (Mg-Pb) and a soapstonebone ash-lead body (Mg-P-Pb).  He has also found that three refractory recipe types were used at the Limehouse porcelain works from 1746-early 1748, based on three previous published works by Freestone, Owen, Jay and Cashion.  Work by Ross has finally recognised the long-rumoured presence of a Limehouse soapstone body only.  ‘Current research questions whether this soapstone – bone ash body was ever made at Limehouse and at least two other factories operating in this general time period need to be considered,’ he says.

After some eight years of research and chemical analysis Ross and coworkers (Daniels and Gael Ramsay) can claim to have dated and attributed the most significant conundrum in current English ceramic research, namely the George II porcelain busts and associated wall brackets. Ross points out that in order to understand these magnificent Mg-P-Pb and MgPb busts and historical wall brackets one needs to interpret the symbolism contained in both bust and bracket. Whilst the English ceramic establishment has yet to comment on this new research, Ross has little doubt that this major conundrum has finally been solved after some 200 years of discussion.

In order to confirm his dating Ross spent several days at the analytical facilities, Monash University, where he undertook non-destructive analyses of various ceramic items including material produced at the pottery works of Whitehaven, Cumbria.  ‘This area has made a major contribution to English pottery output including English creamwares,’ he claims. English ceramic experts have failed to understand that there were two main branches of the illustrious Wedgwood family with the Aaron Wedgwood branch migrating to Cumbria in the late 17th C. A monograph on Whitehaven creamwares is being prepared for publication as of January 2015.

In November 2014 Ross and his wife and co-researcher Gael were invited to speak at ‘Science Express’ at Te Papa Museum in Wellington.  ‘We were able to show how recent forensic analysis of 18th century porcelains is challenging accepted wisdom about their origins,’ says Ross.