Ashes to ashes, dust to diamond 

When a passionate rock nerd with a wicked sense of humour passes away, flowers don’t quite cut it. There’s a more fitting tribute.  

Dr Matthew Valetich, a PhD graduate from the ANU Research School of Earth Sciences (RSES) and beloved member of the university community, died unexpectedly at just 35-years-old in March.   

At Valetich’s memorial service, which captured his sociable, larrikin spirit, hundreds of guests sang along to his favourite party tune, Red solo cup. They paid homage by bringing rare rocks, ancient corals and even a megalodon tooth fossil—together forming a wonderful geological collection of more than 300 items. 

These uncommon tokens of love and remembrance were a nod to Valetich’s profession as a petrologist—a type of geologist that studies the processes forming and transforming rocks.  

In the days following the service, fellow petrologist and former PhD co-supervisor Dr Antony Burnham had another idea about how to honour Valetich. 

“One evening after Matt’s service I was thinking ‘I wonder what his ashes would transform into under a high-pressure experiment, like those he used to do for his PhD?’,” Burnham recalls. “I thought ‘I bet Matt would’ve been interested to try that out’.”  

During his PhD, Valetich focused on a special type of lava called boninite, which occurs when one tectonic plate starts pushing underneath another. 

“Matt was keen to understand what happens in that kind of unusual geological environment, which is depleted of elements like copper and silver,” Burnham says. “His research was filling in our background understanding of what moves these types of metals around geologically.” 

Valetich tried to simulate these volcanic conditions in the lab by doing elaborate experiments. Much of his PhD was spent crafting intricate components for the experiments by hand and with traditional tools in an RSES workshop, which looks like it’s straight out of the 1950s. 

He would make tiny platinum capsules and fill them with rock powder and other mineral layers.   

After making these platinum capsules, which Burnham describes as “like little jam jars”, Valetich would expose them to extreme heat and pressure in a press. 

For Burnham, doing this same experiment with his friend’s ashes seemed fitting—it matched with his research and enthusiasm for science.  

“I think Matt would have found it quite funny as well. Black humour was very much his style.”  

Sentimental science  

While Burnham was confident Valetich would have approved of the experiment with his ashes, he did sense check that it wasn’t going a step too far. 

“Before I suggested it to Matt’s wife Lou, I floated the idea with his best friend Nik, just to double check I wasn’t completely out of line,” Burnham says. “He wrote right back and said ‘yeah, do it’.” 

Fortunately, Louise ‘Lou’ Adena—who has worked across ANU for almost a decade as a professional staff member—was also a big fan of the quirky proposal and the way it mixed science and sentiment.  

“Matt found a second love with geology and he was so passionate and excited about researching rocks,” Adena says. “He also had an irreverent sense of humour and would have loved that we honoured him by turning him into one of the rocks he spent three years studying.” 

Apart from pursuing the scientific curiosity he and Valetich shared, Burnham was keen to give Adena and her two-year-old twins, Harrison and Niklas, “something a little bit special, that no one else really has, to remember Matt by”.  

He wanted to produce a rock that resembled a diamond—tough, a bit sparkly and very precious—that would be a treasure Adena and the boys could have forever. 

However, he wasn’t certain how long it would take to successfully turn ashes into something like a diamond. To be sure, Burnham did a trial run with his own grandmother’s ashes. 

“I was really pleased that after about 12 hours I achieved the result I was looking for,” he says.  

A little muscle and a lot of love 

So, what ingredients do you add to ashes to make a precious gem?  

First, Burnham delicately filled a platinum capsule with Valetich’s ashes and welded it closed. He then placed it inside a series of cylindrical jackets made of magnesium oxide, graphite, Pyrex glass and table salt. 

In this tiny nesting doll of elements, each concentric layer has a role in creating just the right environment to transform ash into rock.  

‘Cooking’ a precious gem also requires heat and pressure—the amount of pressure found 60 kilometres within the Earth, not six feet under.  

That’s why Burnham turned to the oldest piston cylinder press at RSES, which can replicate the pressure deep within Earth. 

They say that good cooking also needs love, so he invited Adena, Valetich’s two best friends and former RSES colleagues—including his mentor and PhD supervisor, Professor John Mavrogenes—to gather around the press and get this special experiment going. 
 
“Matt was so keen to do experiments that he used to get to work at sunrise and have a high-pressure experiment finished before I even arrived in the morning,” Mavrogenes says. “I can’t think of a thing he’d prefer doing right now than getting in a platinum capsule and travelling 60 kilometres underground. We can see him smiling from here.” 

With its analogue dials, big traffic light buttons and instructions handwritten on the machine in marker, the press doesn’t look like a high-tech gadget.  

But its age has an added charm—pressure is pumped manually by pulling a large yellow lever. Each taking a turn at pumping the lever, everyone who attended the experiment contributed a little muscle and a lot of affection to the process.  

“Once I put a piston in and a plate on the top of the cylinder of ashes and elements, everyone added a bit of pressure by pulling the hand lever,” Burnham explains. “We left it to cook overnight, squeezing within this confined, heated space. As hoped, the next day I discovered our precious gem in its place.”  

The last laugh 

A petrology pressure plant is a strange setting for Friday afternoon drinks, but once the experiment with Valetich’s ashes was activated, corks were popped, cans cracked and hearty toasts made.  

“Matt was so passionate about the science and wanting RSES to do well,” Burnham reflects. “Once he finished his PhD and moved to industry in 2020, he was a strong advocate for academia and research.  

“Industry often doesn’t really engage with universities all that well, but Matt was always proselytising the value of staying in touch with academia, up to date with current research and even driving some of that research.  

“He was also just such a fun person to chat to and would always offer some perspective you may not have thought of, whether you were having a problem in your personal life or research. He was a very experienced and skilled guy to have around—we miss him.” 

Once the gem was cooled and polished, Burnham cut it in two and mounted the halves in their platinum casing within rounds of epoxy resin, gifting them to Adena. 

“It was a pretty sweet moment, opening the box and seeing my Matt immortalised as a ‘diamond’ encased in platinum,” Adena says. “It’s why we had platinum wedding rings — as a nod to his PhD, which he was so incredibly proud of—and I can see his cheeky smile lighting up the room at the thought that he is now a pretty cool rock.”  

Science can affirm what we know or be ground-breaking; it can be practical or a spectacle; and it can be deadly serious or seriously funny.  

If he knew that his geology mates had used their shared knowledge and passion for science to turn him into a rock, Valetich would be having the last laugh.