One of the most unusual and rare artifacts was found accidentally.
During the search of gem shop owners for the new showpieces in the Coso Mountains (California), in 1961, they collected one very special piece. That was the Coso “spark plug”.
They became aware of its uniqueness when they started cutting the rocks with an intention to find crystals inside. Not just that one of them didn’t contain crystal, it represented a kind of a mechanical device, something like a spark plug.
Further examination of this piece showed that there was a magnetic rod and a metal spring inside the porcelain cylinder surrounded with copper rings, along with another, unidentified component.
As scientists point out, possible age of this geode is 500,000 years and according to analysis, this device had been sunken into the seawater for a long time. Everything about this object is unusual and difficult to explain. The questions about its origin and the owner are still open. Nobody can rule out terrestrial nor extraterrestrial possibilities.
Some people claim that this artifact is the proof that pre-flood civilization existed, but skeptics decisively disagree.
However, this artifact disappeared eight years after being discovered, so no thorough examinations were performed on it.
The only thing we can do not is coming up with some new theories, but without the possibility of proving them.