Essentially untested
Psychometry
Psychometry is the claimed ability of reading the history of an object by holding it. It has been tested — Almost none under controlled conditions. No controlled body of evidence exists either way.
The experiment
Almost none under controlled conditions
Untested is not the same as disproven, and it is worth keeping those apart. What can be said is that the claim has been available for testing since 1842 and has attracted almost none.
That makes psychometry the oldest unexamined claim in this list — 184 years old and counting. Compare it with the ganzfeld experiments, which have produced hundreds of sessions since the 1970s, or with the AWARE study, which installed physical targets in 15 hospitals to test a claim made in the same century. Psychometry would be trivially easy to test: hand a reader ten objects with known histories and ten without, keep the histories from everyone in the room, and count. The design costs nothing and takes an afternoon. Its absence is the informative part — a claim this testable staying untested for 184 years says something about who has wanted to find out.
Where the word comes from
Coined in 1842 by Joseph Rhodes Buchanan, an American physiologist, who meant it as "soul-measuring".
Terms in this field are younger than they sound. Most were coined between 1840 and 1930, in the Spiritualist and Theosophical revivals, and then presented as ancient. Dating them is the cheapest reality check available.