If you want to ride the waves along this rugged coastline, you’re going to need a very, very tiny surfboard. What appears to be a gull’s-eye view of the ocean crashing on a rocky shore is actually a microscopic image of a gem called a prase opal. The green part of the specimen is the opal, while the brown “coastline” is the host rock, “a silica and iron-altered serpentinite,” says professional gemologist Nathan Renfro, who captured the image. “The turbulent-looking white areas are most likely small fluid inclusions that make…
