They covered "expected" ages ranging from 1 to 600 million years.
Between 19 several teams made a number of radiometric measurements, and the results clustered around three ages-1.8 MY, 2.4 MY, and 2.6 MY.
Each team criticized the others' techniques of rock sample selection.
Studies have been made of submarine basalt rocks of known recent age near Hawaii. Yet it was found beneath a layer of the volcanic KBS Tuff that had an accepted radiometric date of 2.6 MY (millions of years old).
Leakey declared that the skull was 2.9 MY, and said that it "fits no previous models of human beginnings." It was named KNM-ER-1470 (for Kenya National Museum, East Rudolf, #1470).
Marvin Lubenow gives a good description of the ten years of controversy surrounding the dating of this skull.4 In the first attempt at dating the KBS Tuff, Fitch and Miller analyzed the raw rocks, and got dates ranging from 212 to 230 MY-the Triassic period, vastly older than expected.
Because mammal bones had been found below this stratum, they said these dates were obviously in error because of "the possible presence of extraneous argon derived from inclusions of pre-existing rocks." Even though the rock looked good, anything older than 5 MY was obviously wrong in view of their knowledge of the "sequence of evolutionary development." Meanwhile a team from the University of California at Berkeley, led by G. Curtis, analyzed several KBS pumice rocks and found some that were around 1.6 MY and some that were about 1.8 MY.The "correct" answer is chosen on the basis of stratigraphic sequences, that is, what kinds of fossils are buried nearby.Of course, the fossil dates depend on the assumption of evolution."How can creationists expect people to accept a young earth when science has proved through radiometric dating that the earth is billions of years old?" This article addresses that question, which represents the thinking of a large number of people today.Most people, even the experts in the field, forget the assumptions on which radiometric dating is based.