The Coso Artifact

The Coso Artifact is an item known as an “out of place artifact.” Out of place artifacts are essentially modern objects found in places where they do not belong, hinting at the possibility of modern technology having been around long before modern man developed it. In the case of the Coso Artifact, the item was found inside of a stone or lump of hardened clay. Proponents for the Coso Artifact as an out of place artifact say that the material in which it was discovered is too old to have held such an item. Estimates put the material at around 500,000 years old. However, there is another side of the story.

coso artifact

The Coso Artifact

The Coso Artifact was found by rock and geode hunters Mike Mikesell, Virginia Maxey and Wallace Lane. On February 13, 1961, the trio was hunting for geodes to sell in their gift shop. They hunted in the area of Olancha, California and then brought their finds back to the shop to be sorted and cut. When one of the “geodes” was cut, a cylinder of metal and ceramic was found inside. One of the discoverers of the Cos said that an archaeologist dated the material to 500,000 years ago. It was also said that it might be hardened clay and that it also contained what looked like a nail and a washer.

The date of the Coso Artifact relies on the assumption that it is a geode. The only known thorough physical examination of the Coso Artifact found that the material was too soft to be a geode. It also lacked the telltale quartz crystals found in crystals. Some softer materials can form around a modern item relatively quickly, whereas a geode cannot. That renders the age estimate not necessarily incorrect, but based on a faulty belief. The most telling part of the examination came with an x-ray of the item inside. It revealed that the metal was a cylinder with a screw-like item on one end and a flare on the other end.

Since the time of that investigation, the Coso Artifact has disappeared. The three individuals who found it are not talking about it and one may have since passed away. Nonetheless, the first investigation and the photos (including x-ray photos) that resulted have made it possible for experts to make some interesting discoveries about the item. Not only is it widely known that the photos do not show a modern item inside of a geode, the item inside the geode has been identified.

Pacific Northwest Skeptic Pierre Stromberg took an interest in this supposedly out of place artifact and decided to look into it. Unable to use the Coso Artifact itself as a point of reference, he used the photos and x-rays that were taken of the item decades earlier. It had been proposed that the item was a spark plug, as it displayed many of the characteristics of a spark plug. However, the screw-like end posed a problem. He contacted the Spark Plug Collectors of America, asking them to identify it, if possible. He received word back that the item had been positively identified as a 1920s Champion spark plug. There was no doubt in the man’s mind and other spark plug collectors have confirmed that the Coso Artifact is indeed a spark plug, just designed differently than the spark plugs we use today.

The spark plug identification, along with the nail and washer mentioned by one of the people who discovered the Coso Artifact, the idea of it being a piece of hardened clay that formed in some kind of work yard becomes the most logical explanation. A professional examination of the Coso Artifact would certainly prove or disprove that hypothesis in a matter of minutes. Unfortunately, that is not currently possible. It seems unlikely that it was a hoax, given the hands-off approach that the discoverers have taken over the past few years. It seems it was simply mistaken for something that it was not. In fact, even Maxley said that was a possibility.

Coso Artifact, retrieved 1/28/12.
Stromberg, Pierre, The Coso Artifact, retrieved 1/28/12.

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Shelly Barclay writes on a variety of topics from animal facts to mysteries in history. Her main focus is military and political history. She is a writer for the Boston History Examiner, Military History Examiner and the Boston American Revolution History Examiner. She also writes for a local historical society newsletter.

Historic Mysteries