500,000 Year-Old Spark Plug Found in Rock: The Coso Artifact

The Coso ‘Spark plug’ is one of the most interesting and anomalous artifacts ever discovered. Its story begins one February morning in 1961, when the owners of a gem shop were out looking for new exhibits in the Coso Mountains of Eastern California. Little did they know that, among the geodes they collected was a … Continue reading 500,000 Year-Old Spark Plug Found in Rock: The Coso Artifact