Cast concrete counter tops with various items embedded into them are becoming almost as popular as granite. We just had ours created. It features quartz crystals that I collected from tailings in Jessieville, Arkansas, a few relatively spectacular beach pebbles, and numerous water smoothed stones of banded trap rock. We're delighted with our new kitchen counter despite visual differences between the end result and our original vision. These discrepancies were not big surprises, much less disappointments. They resulted when the finished product was polished smooth. This removed approximately 1/16 inch of original counter top, eliminated striations and occasionally altered the outlines of some crystal faces. It also diversified the shapes of numerous trap rock pebbles
One quickly noticeable surprise was how shadows darken a clear embedded crystal even when touched ever so slightly by one's finger. By retaining their original shapes, the beach pebbles, all with diameters of less than an inch, attractively retained their shapes. The trap rock pebbles, on the other hand, which were always larger than the beach pebbles, tended toward a range of eclectic shapes with portions covered by concrete. These eclectic shapes, however, proved more pleasing than had their shapes remained as we had last seen them. They definitely proved an antidote to boredom.
In conclusion, we have a few tips that could prove pertinent helpful to anyone who undertakes a project similar to ours. Very important at the outset is that whatever minerals, crystals, gems, stones, or rocks are used, their hardness should equal seven or higher on the Moh's hardness scale. With respect to minerals, this could pretty much limit you to quartz, garnet, tourmaline, and corundum. Color scheming, which depends upon personal taste, also merits consideration. Early on, I was eager to to contribute about a dozen amethyst crystals and a limited amount of blue corundum sapphire, but Nina nixed it. Instead our quartz crystals were transparent or milky with the exception of a small number of dark grey-yellow citrine crystals. If we'd had some on hand some loose smoky quartz crystals, however, they also would have worked great.
While the trap rock pieces ran a gray scale, The beach pebbles, all translucent quartz, came in hues that ranged from yellowish to brownish, a few with a reddish cast. As effectively as everything worked together, our only regret was not having more of them. And now that the project is complete, I agree with Nina that including any blue, green or purple crystals would have distracted from from our desired level of cohesiveness.