I’m trying to learn my microscope. These are single focus shots; as I learn more I will get to know photo stacking which will result in the entire field being in focus. If I do it right. If you enjoy these photos of California sand, there’s pictures of Hawaiian sand at my rockhounding site: https://southwestrockhounding.com/2019/09/14/hawaii-in-a-bottle/
I bought this Pfeiffer beach sand from RC at Geological Specimen Supply: https://geologicalspecimensupply.com/
Here’s what RC says about this sand:
“Sand is derived from whatever material is available. In this case, the probable source of this sand is the Big Sur River. Its watershed contains both garnetiferous schists of the Franciscan Complex and granitic rocks of the Salinian Block, where diorite contains a significant quantity of garnet. Pfeiffer Beach is primarily composed of quartz sand, but in areas the garnet has been concentrated by wave action. This sand is roughly half garnet and half quartz. We could have run it through a concentrator to increase the garnet content, but prefer that students see it as it was found on the beach.”
“A good question for students is, ‘What’s the pink stuff?’ This can lead to a discussion of what makes up sand. It’s unlikely they will have seen sand with garnet in it. It is slightly more dense than the quartz that makes up most of the beach sand in the U.S. The dark grains in this sand are derived from the Franciscan Complex, a chaotic assemblage of rocks that were scraped off the Farallon Plate as it subducted under the North American Plate during the late Mesozoic.”
Note the lone purple grain in the last photo. I’m trying to identify it. These are uncorrected for color, photographed under halogens and a little white LED. The white balance is driving me crazy. The garnet may ranges from ruby red to pink. The clear to white grains are quartz.
What the sand looks like before it is photographed. Just to give you a sense of scale.
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