Some time ago, while driving along Highway 15 south from Morton I saw a flat-bed semi; at least 22 tires were stopped, ready to come onto the highway from Thomas Road. As the rig pulled onto 15 heading south, I could see from its stacks that the driver was using every gear in the box to get up to highway speed. What might a big rig haul from Thomas Road that could be so heavy? As I came closer, I could see he was toting two relatively small blocks of rough-cut granite; blocks likely destined for the diamond saw; monument-grade granite, beautiful, heavy and almost eternally hard. For decades, quarries near Morton have provided fine granite to be crafted and polished into monuments; pink granite from Morton; white granite from Vermont; black granite from Norway. In recent years, some Morton pink has also been crushed and used to face concrete from here to Las Vegas.
A billion years ago during the collision of Laurentia (Canadian Shield) and Amazonia (Brazilian Shield), a great range of mountains was heaved up. Deep in the roots of those Grenville Mountains, Westport Mountain Vortex, Lyndhurst Vortex and others took form. Eventually this collision and mountain building slowed and ceased. The Lyndhurst Vortex started to chill out. Over months, maple syrup kept in your refrigerator will crystallize. Over eons, the Lyndhurst Vortex of super hot magma slowly cooled through 1 200 degrees C. Crystals of minerals formed. Atoms of oxygen, silicon, aluminum, iron, magnesium and a few other friends cozied together into crystals for the rest of time; or until the next round of continental collision hits the neighbourhood. Crystals of dark-coloured ferro-magnesium minerals such as hornblende and biotite formed and floated in the cooling vortex. Biotite is one of the mica family of minerals. Its crystals are 6 sided, thin and layered like pages in a book. In the historical past, local “cotton-bag” miners carefully excavated “books” of mica from many small pits that once dotted the Frontenac Axis. Unburnable, it was used for fancy fronts of stoves and in early radio tubes and toaster elements. Without proper eye protection some cotton bag miners went blind due to the effects of tiny mica fragments.
Further cooling through 1 000 degrees C. in the Lyndhurst Vortex and atoms of aluminum, silicon, oxygen and some friendly potassium took up permanent residence together in pinkish crystals of orthoclase, one of the feldspar family of minerals. All the many feldspars have slightly squashed box crystal shape. The largest crystal of feldspar ever recorded was mined in the Ural Mountains of Russia and weighed over 100 tons. That’s a lot of tomb stones! Generally speaking, the slower and longer the cooling phase, the bigger the crystals can grow. If crystals larger than 1 cm. form, you have a pegmatite. Thousands of tons of very pure feldspar were mined near Desert Lake north of Sydenham and shipped to the U.S. to make fine porcelain. It is rumored that glass bottles filled with moonshine were often hidden in those south-bound railway cars during those prohibition decades.
There are said to be over two thousand minerals that make up our planet. You can see many of the “orchids of the mineral realm” in the museum of the Department of Geology at Queen’s University. Our Frontenac Axis is one of the greatest natural laboratories of minerals on our planet. Each mineral such as hornblende, biotite mica or the members of the feldspar family has its own special chemical recipe, no matter where on earth it is found. Each mineral will have its own distinctive shape decreed by how its atoms lattice into a solid. Sodium and chlorine form cubic crystals of the mineral halite, otherwise known as common salt, the stuff on potato chips and winter roads. From softest talc to hardest diamond, each mineral will boast its own distinctive hardness. But colour? Don’t count on it! The feldspar family of minerals comes in a wide variety of colours. Perthite can be salmon pink to green. One guess where you might find Perthite. Labradorite, also a feldspar displays a beautiful rainbow effect. Beyond the feldspars, Jacques Cartier thought he had found gold along the St. Lawrence River. But poor Jacques had found fool’s gold, mere pyrite, just iron and sulphur in gold-coloured cubic crystals, so hard that it fails the simple tooth test. Maybe ol’ Jacques was toothless.
As the temperature within the Lyndhurst Vortex cooled below 700 degrees C., not much was left but silicon and oxygen to settle down. They gelled into glassy silica and filled the gaps between the crystals of hornblende, biotite and feldspar, much like gelatin fills the gaps among the chunks of pineapple and peach in a jelly salad. Voila! The seething Lyndhurst Vortex over eons of time became a magnificent and very solid pluton of granite rock. Any rock, be it granite or limestone is a somewhat indefinite mixture of several to many minerals. Over eons of time, the Grenville Mountains eroded away. As this enormous weight and pressure was removed, the Lyndhurst granite expanded and cracked along jointing planes. You can see these natural cubes in the rock cuts beside Highway #15 near Morton and Seeleys Bay.
As silicon and oxygen are the most abundant atoms on our planet’s surface, so their combination forms our most common minerals, the silica family. Within the Lyndhurst Pluton, heat, pressure and blending was fairly uniform so a fairly uniform granite resulted. But beyond the pluton near Red Horse Lake, some silica had space and freedom to fill cracks and cavities in the surrounding host rock. There an amazing thing happened. Quartz crystals with characteristic 6 sides and pointy ends took shape. Anywhere in the world, crystals of quartz have this same geometry. Clear and perfect crystals of quartz were fashioned into grand chandeliers for tsars and emperors. Near Thunder Bay, a little bit of iron impurity in crystals of quartz turns them into beautiful purple amethysts. Quartz crystallizes at about the same temperature that metals like gold, silver, copper, lead and zinc go solid. Sour-dough prospectors knew the odds were good that these valuable “base metals” might be found in veins or “leads” with quartz. Such was the case of shiny cubic crystals of galena once mined near Black Rapids south of the Lyndhurst Pluton. Galena is a source of lead metal, especially important during a World War. A trace of gold can be found near Farren Lake north of the Westport Pluton.
A very different set of conditions and silica became non-crystalline red jasper along the shores of Lake Superior, or banded agate in the Maritimes. Ancient ancestors and native people around the world shaped tools and weapons harder than finest steel from flint (nodules of silica) and obsidian (volcanic glass).
Quartz-rich rocks weather into sand grains hard enough to resist eons of wind and wave. Modern media; “On the Beach.”? Australian silica sand. “Lawrence of Arabia”? Camels traversing dunes of silica sand. Beach Volleyball in the Beijing Olympics? None but the finest imported silica sand. Then, who was watching the sand? The majority of beaches and dunes of our planet are of grains of silica. The Lions Beach at Westport and the Sand Banks near Picton come to mind. It is very appropriate that silica sand was “the sand of time” in antique hour glasses. The silica sand of Cambrian beaches and dunes became layers of Nepean sandstone. Near Elgin, British quarrymen marveled at its quality as they masoned the ashlars for the great dam at Jones Falls and the nearby locks of our Rideau Canal, now a World Heritage Site. More recently, mining speculators have had their lustful eyes on the very pure silica sandstone found in the western part of South Burgess. Silica was melted and tinted by Tiffany to make a beautiful stained glass window in St. Mary’s Church in Newboro. It was blown into shape, etched or enameled into that prized crystal vase on Granny’s shelf. Now it is melted and gelled into panes for the windows in your home. It is shaped into Mason jars, Champagne bottles and thousands of other things of our modern ways.
Back to those natural crystals of quartz mined near Red Horse Lake during World War II. It never ceases to amaze me that this most common mineral has some truly uncommon qualities, hidden talents and electrical traits. Take a good crystal of Red Horse Lake or Brazilian quartz, wrap it with some 1940’s electronics and you could detect sound waves from German U-boats lurking in the Atlantic. Some of us of more mature age once sent our 2 box tops and 2 dollars for crystal radio sets as advertised in the latest Superman comic books. The mailman brought a kit including a magical crystal of quartz, some copper wire and a simple amplifier. Battery not included.
It gets better. A tiny crystal of pure synthetic quartz vibrates at a constant rate for ever. Voila! Seiko watches. Centuries of Swiss spring-powered time pieces went the way of the Stanley Steamer. It gets even better. Take a tiny, thin chip of ultra-pure, synthetic silica, spice it with some exotic atoms, circuit map it with gold and micro-tech. Voila! You have a computer chip, the workings of a talking teddy bear or a Blackberry, a GPS unit in your car or a space craft navigating the universe. All this from kin to that same last and lowly-born natural glass which a billion years ago gelled the gaps between the first and noble-born crystals in the Lyndhurst Pluton. Because it fills the gaps and smothers the beauty of other rock-forming minerals, some decry silica as the “banana slug” of the mineral realm. I like to think of quartz as the “Cinderella” of the mineral realm. She ventures from the most modern palaces in “Silicon Valley North” and South. She has a chippy relationship with the richest princes of our modern world, like Bill Gates. And didn’t Cinderella wear silica slippers? Or just one?
Yes, right out of Mother Nature’s Rock and Roll Cook Book. Bring to a raging boil, then cool slowly some clear silica, some colorful feldspars, some dark ferro-magnesiums. Add a few salts and spices to taste. Then savor the view and appreciate the miracle in rock from Rock Dunder and Spy Rock, indeed the identity and anchor rock of continents. We take it for granite!
Geology/Natural History tours are sponsored annually by the Bastard and S. Burgess Heritage Society on the third Sunday afternoon of September (subject to weather) when we look at some of the sites of significance in our local and very rich natural history.