Author Topic: John Christopher Rucklidge  (Read 270 times)


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John Christopher Rucklidge
« on: June 19, 2021, 07:10:16 AM »
John Rucklidge passed away on May 7, see the obit written by family:

His scientific achievements did not begin or end with EPMA and standards for microanalysis.  I will post more info next week.
« Last Edit: June 19, 2021, 08:47:54 AM by John Donovan »


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Re: John Christopher Rucklidge
« Reply #1 on: June 24, 2021, 02:26:18 PM »
This is a subset of John’s achievements—only those directly connected with microanalysis. 

John attended Cambridge University—starting in Physics but changing to Geology during one summer semester because Geology had field trips including an IGY sampling cruise to the High Arctic.  Professor Deer at Cambridge pointed  John to colleague Prof. Howie at Manchester, and John completed his doctoral degree at Manchester U under Prof. Zussman.  John’s 1964 thesis was half  microanalysis using a first-generation probe, and half single crystal structure determination.   

John was recruited for the famous Oxford Greenland expedition described by Simon Winchester in Krakatoa.  That collecting trip perfected John’s eagle eye for tiny secondary minerals.  Rucklidgeite was a later discovery.  He joked in 2012 that rucklidgeite was not a suitable material for a standard.

John also did a postdoc in the University of Chicago’s Cloud Physics Lab.  I have attached a copy of his paper from that work using TEM which is still cited for its good data.  He became familiar with J.V Smith’s work and thinking.  Decades later, John’s lesson about Dr.  Smith’s feldspar thermometry described exactly what the rare earth pentaphosphate syntheses also did. From Chicago, he met former colleagues working at the University of Toronto and was hired.  John wrote of his early experiences in the 2016 Earth Sciences Alumni Newsletter, link here

 John used that ETEC for teaching, and he wrote several generations of control-data reduction software including his 2008 Windows version.  The ETEC was the prototype of John’s AMS sample stages, and with a little tweak, also did electron beam labels.  People looking at the video screen attached to the microscope would say “Hey—those are WORDS in there” and I would invite them to take a closer look. 

John did not abandon his collaboration with physicists, and this led to him becoming a founding member of IsoTrace, the accelerator mass spectrometry lab located deep under the Physics complex.  They built the science and the lab from pieces and stuck them together as required.   Neither John nor his colleagues ever went around telling people that they were the Fathers of AMS--that was left for us to discover for ourselves.  During the time that I worked at IsoTrace, Prof. Harry Gove was still active, using IsoTrace for research after NSF moved  the Rochester AMS lab  to Florida.

The demand for reliable calibration expanded with the new science.  John taught one student to make serial dilutions of tracers in copper down to ppm levels.  Another student completed a research project on I-129 in zebra mussels on pipes of nuclear reactor cooling systems.  John routinely took a specimen from SEM to EPMA to AMS, and that meant he could  work with meteorites.   
John’s contributions to AMS  included the data collection software and the ion source-sample stages that were modeled on SIMS.  John was working on a new-generation ion source when his collaborator Linas Kilius died suddenly in 1996.  John told me later that there was nobody to take Linas’s place.  John retired from his professorship in 1998 but he attended thesis defenses as a member of  the University Senate  whenever he was in Toronto.

And just for fun, he chaired and ran the 1998 International Mineralogical Association  meeting in Toronto. John then sat down and expanded the standards-for-microanalysis business that he had started in 1969 when nothing was available.  I once asked him about the quantum leap of  assaying  moon rocks, and he admitted there was “much excitement” even at a distance. John acquired the best part of Charles Taylor’s collection at auction in 2000 when Taylor was in seriously poor  health and could not continue the business with the help of longtime assistant Jerry Weatherford.  The collection went into e-commerce, with a webpage for each material that was highly cross linked to other webpages.  John wrote the software to do this painlessly.

John also commissioned the synthesis of rare earth pentaphosphates three times.  The first two attempts  did not succeed, but he was willing to try a third time when I came along in 2004.  That project was delayed for a year by an icy sidewalk, but it was completed to commercial distribution. We validated the production of mixed crystals (based on Drake’s glasses) in a 2010 AGU poster.  The mixtures had to be redone once the best host was validated, and time ran out.

John handed the standards manufacturing over at the beginning of 2013.  John always expressed the strong desire that his company continue into the indefinite future.  John made a plan that would allow him to ease out at the age of 75, but he ended up not “enjoying the delicious sense of freedom from Astimex” until he turned 80.  I cannot imagine John being happy at all when things shut down about two years ago. I cannot think of any reason that the business had to be shut down--some good advice would have allowed another transition to take place.  There were several people  who had worked with John and who the skills to keep it going.  I guess whoever owned the business did not feel any connection to the illustrious history.

John was a polymath genius who felt no need to make a lot of noise.  He once said to me “you know, Astimex is more than just standards”.  I said ”I had a math teacher who asked us how many testicles an octopus has.  Do you mean like that?”  He grinned and said “something like”. One of John’s forebears was the Revenuer of Islay and something from that island will be my toast of choice. 

(I realise this is long.  A long and productive life leads to long lists)
« Last Edit: July 12, 2021, 11:46:28 AM by crystalgrower »