Coso Artefact

X-ray imaging revealed an internal hexagonal sleeve and ceramic centre. Subsequent analysis identified it as a 1920s Champion-brand spark plug encased in mineral concretion.

Honesty obliges us to record this one as resolved, and not in favour of the marvellous. The object was found near Olancha in 1961 by rockhounds who believed they had cut into a geode and uncovered a manufactured artefact embedded in stone hundreds of thousands of years old. The claim drew the attention of those who see in such finds evidence of lost or impossible technology. It does not survive scrutiny.

A careful investigation, led by Pierre Stromberg and the geologist Paul Heinrich with the cooperation of spark-plug collectors, matched the object against parts catalogues and identified it as a 1920s Champion spark plug. The encasing material is not a true geode but an iron-oxide concretion of the sort that can form around a hard nucleus in a matter of decades, not aeons, when iron corrodes in the right conditions. The hexagonal sleeve, ceramic insulator, and metal shaft revealed by X-ray are exactly those of an early twentieth-century plug. Where a conventional explanation exists and is well evidenced, we say so plainly: the Coso artefact is a piece of ordinary industrial hardware, naturally entombed and mistaken for something older.