sand - garnetiferous sand composed primarily of quartz and garnet from Pfeiffer Beach, California - 250 ml display bottle with ground glass stopper

Sand is derived from whatever material is available. In this case, 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