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Rocking Out at the ROM

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The ROM’s Janet Waddington sketching out our fossilized creature.


In one Calvin and Hobbes strip, the pair are walking through the woods when Calvin spots a rock on the ground and stops to pick it up. “See how smooth it is?” he remarks to Hobbes. “It probably took eons to get like that. It’s a sedimentary rock, formed by sediment deposits, as opposed to say an igneous rock, which is volcanic in origin.”
“You sure know a lot about rocks,” replies Hobbes.
“You bet,” says Calvin. “Ballistic missiles from God I call ‘em.”
As usual, Calvin’s knowledge stems from his own morally questionable intentions. But he’s right about one thing: rocks are awesome. It’s a sentiment that we had the pleasure of sharing this past Wednesday with the rock experts who run the Royal Ontario Museum’s Rock, Mineral, Gem, Fossil, and Meteorite Identification Clinic.


Conceived as a way to help museum visitors ID their discoveries, the clinic, which is run once every two months, is in its thirteenth year. Think Antiques Roadshow—except that it’s for rocks only (no stone artifacts), and there are no appraisals.
“We usually get local stuff from the Toronto area,” explains Janet Waddington, a self-described rock aficionado and the ROM’s assistant curator of Invertebrate Palaeontology. “Sometimes we get things that people have picked up on holidays. They’re harder, because we’re not familiar with the geology.”
The clinic also gets its fair share of visitors who come in with what they hope are rare gemstones or meteorites. “Some people think they’re going to put their kids through college on the proceeds of their rock,” sighs Waddington. “When, usually, it’s the most common thing you could ever find. We’re not allowed to appraise things, but we can say that it has no market value.”
In fact, staff say that they’ve seen so many so-called “meteorites” over the years, they’ve taken to calling them “meteor-wrongs.”
Usually, explains Vincent Vertolli, the ROM’s assistant curator of geology, the meteorite look-a-likes turn out to be slag, a smelting byproduct, which, because of its ridged features, often resembles the real thing. And since it’s commonly used as railway-track bedding and can be found near most mines in Ontario, it’s regularly brought in to clinics by people who mistake it for something more exciting.
“We had a fellow who came in, and he had found a stone at the bottom of his swimming pool,” laughs Vertolli. “He swore that it had to be a meteorite, as how the hell else could it have gotten into his swimming pool? So I asked him, ‘Do you have a rail line nearby?’ And he’s like, ‘Oh yeah, there’s not one too far away.’ Some kid probably just picked up some slag and threw it in his pool.”
According to staff, meteorites aren’t easy to identify, so even when they do get a rock that fits the description, they usually have to run some tests, and only rarely do the results come back positive.

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Our first fossil.


Unfortunately, Torontoist has yet to discover any meteorites (or even any slag for that matter). So instead, we brought to the clinic two fossils from Etobicoke’s Mimico Creek.
As Waddington explains, our first discovery contains the fossilized shells of a squid-like predator called the Nautiloid cephalopod.
“These are very very common fossils,” she says. “Where you get one, you usually get lots. These are common from the west end of Toronto. The environment was right there. These things were hanging out there, or were nearby, or got washed in there.”

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Our second fossil.


Our second fossil, she continues, features an imprint made by an Ambonychia, a type of clam that was common to west Toronto and the rest of the Georgian Bay Formation.
Both of our fossils, she notes, also contain little black bits from an extinct arthropod called a Trilobite, which lived just about everywhere on the sea floor and molted quite frequently, making their fossils extremely common.
Finally, she puts the age of both our fossils at about 445 million years, placing them in the Ordovician period. To put that in perspective, at that time North America was sitting on its side along the equator and Toronto was in the southern hemisphere.
That we were able to find such great specimens in Mimico Creek is no accident. When it comes to fossils, Toronto has only one king: Etobicoke.
“They come from places where there are rocks exposed, [and] there aren’t that many places in Toronto where actual bedrock is exposed,” says Waddington. “You get the Humber River, Mimico Creek, and Etobicoke Creek—along there the water is actually cutting through bedrock. That’s where the fossils get broken off.”
If you have a rock that you want identified, the ROM’s next clinic will be held on March 23 at 4:30 p.m.
Photos by Stephen Michalowicz/Torontoist.

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