Alberta Lapidary, Rockhound Article #2, thanks again Dick H. ! !

Filed under: Rockhound stories — Gary September 22, 2006 @ 2:01 am



It’s pretty tough being an Alberta rock hound, it’s even tougher being a broke old rock hound living in Calgary.
Then again there are a few rock treasures around and from the east side of Calgary and as far flung as the badlands of the Red Deer River. I have made a collection over the years that would impress most amateur geologists/palaeontologists and most of my collectables were picked within a hundred miles of Calgary. I have a good sampling of local Calgary gravel, which includes most types of rock in the rockhound books, except metals and precious gems. I have collected fossil wood and even bone in the local gravel but most of my fossil bone comes from the badlands and gravels around Drumheller.
My favourite gravel patch around town is the artificially deposited gravel lining of the irrigation ditch, downstream of the weir near the centre of the city and out as far as the bedroom community of Chestermere Lake, about 10 kilometres out of town. The ditch was constructed over 50 years ago and within the last twenty it was revamped and beautified by the addition of more gravel to both banks and a bike trail along its entire length. The gravel comes from either pits south of town along the Bow River or from the Beiseker deposits or both. I know the gravel is mostly from downstream of Calgary because there is Canadian Shield material included with the sedimentary material of the eastern slopes. The Laurentide and Cordilleran glaciers fought a few times for supremacy in the Calgary area and float from each were left around town to be found in the make up of the ditch liner. I like the way the weather has cleaned the ditch gravel and except for the gravel below the water level the rocks have been rain washed, I even have licked a few to get a better view. Most of the rock is unsorted pit-run, so all sizes are present and I have brought home little fragments, pebbles and even a pretty boulder or two. The ditch rock is actually owned by the Western Irrigation District – I assume this to be the Alberta Government – but I can’t say I have picked up much more then a couple of hundred pounds over the years – a couple rocks at a time. Most of the time I’m just out for the exercise – strengthening my ankles for my badlands hikes.
I have found some museum quality stuff in the ditch gravel. Tumbled Palaeozoic marine coral fossils are quite common and I have several samples of fossiliferous limestone with various sea life that when polished make good shelf curios. There are12,000 year old hardened and rounded off glacial lake sediments with snail shells and occasionally you may find a piece of river rounded sandstone with clam shells or their impressions. Some of my best pieces however, are the occasional pieces of petrified wood, which along with granite, schist and gneiss form the continental glacier’s contributions. The glacial float was scooped out of river gravels further north and mixed with our local rocks when the two great glacial masses left their battle scars on Calgary’s landscape.

My best find to date, is a fist sized carnelian agate nodule considered a one of a kind for the Bow River. I have been to the ditch several times before and after this find and can say I’ve never found any thing quite like it. The petrified wood is opalized or agatized or may be crack filled with chalcedony of some sort but never have I seen pure carnelian agate. However, it is not uncommon in Alberta, but according to local rock hounds not much has been found around Calgary . I have found some in the North Saskatchewan and Red Deer River gravels; only small fragments of course, never almost complete fist-sized nodules like my Calgary Agate. I got a write up in the June 2002 edition of the online Canadian Rockhound Magazine, for a one of a kind find.
I shouldn’t ignore the other hard stuff in the gravel that actually polishes quite well either by hand or in the tumbler. The banded quartzite from the Rockies is a favourite and granite pegmatite comes a close second. I have found some feldspar gabbros and crystals that are pretty and will pick up schist to shine back at me from my rock garden.
I could give a course in local geology sitting on a lawn chair under my big blue spruce out front. My rock garden has mostly local things in it, from rusted railway spikes to big old beasties bones. The beasties bones of course are culls from a hefty quantity of fossil dinosaur fragments that I bothered to rescue from erosion. Under my tree is dryer then the eroded slopes of Alberta’s Badlands. Besides, I’m just maintaining some of our natural heritage a little closer to my home – if it’s under my tree you’re welcome to it, one piece at a time of course.
I have an enviable tooth and claw collection and the displays within my walls are wondrous and marvellous to my eye. As I sit hear dissertating I can look up and see my crystal core, my stormy rock, my best bones and a piece of my one and only Calgary Agate. My homemade fountain trickles besides me as I type and on its ledges washed with water is a fair sampling of my collectables. I now realize that even in Calgary you can be surprised at the variety and quality of rocks a watchful eye may pick up around town. After an unusual cold snap the sun is back and the sky is finally blue. I think I’ll head for the ditch, my ankles need a tune up for Thursday in the badlands.

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