Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, California.
(3) There's flexible and even transparent blood vessels, cells, and even and hadrosaur DNA (with a half-life of ~521 years) in dinosaur soft tissue fossils.
Many such lines of evidence (multiplying as at youngearth.com) undermine the claim by old-earth geologists that the plentiful 14c in "ancient" specimens must come from contamination or neutron capture (see below), and this evidence helps to confirm the young earth interpretation of the data below.
P.) are positive evidence for a young Earth (less than 10,000 years old). When the average person hears the term "radiometric dating", he/she most often recalls the radiocarbon method, even though this method is relatively unimportant to most research in geology.
However, this is not out of ignorance on anyone's part.
(1) Significant amounts of short-lived 14c, in quantities far above the least count (margin of error) of our state-of-the-art equipment, is measured in diamonds, dinosaur fossils, marble, giant extinct aquatic lizard, natural gas, coal (and see this paper at Science Direct), and reportedly in oil.