Sandstone Concretion and Sea Anemones. I’ve mashed-up two sketchbook pages here — always wanted to see these two together; for some reason they remind me of each other. On the left is part of a sandstone concretion, a type of mineral crystal, from the collection of the Royal Ontario Museum. On the right is a group of sea anemones that I drew at Ripley’s Aquarium, Toronto. Both graphite pencil.