Fort Rock Cave in Oregon is the site where archaeologists discovered several
Indian sandals, the oldest ever found in Oregon. Analysis of the
14
C content
of the sagebrush used to make the sandals gave an average decay rate of 5.1
disintegrations per minute (dpm) per gram of carbon. The current
14
C/
12
C
ratio in living organisms is 1.3
×
10
−12
, with a decay rate of 15 dpm/g C. How
long ago was the sagebrush in the sandals cut? The half-life of
14
C is 5730 y