SF. Logan's Run - William F. Nolan and George Clayton Johnson, paperback as description

There were too many people, and not enough food.  So they had, in an orderly and systematic fashion, to get rid of some of the people, the old ones, all those over the age of twenty-one.    It was easily done.  In the palm of everyone's right hand was embedded a crystal flower.  In adults, all those over the age of fourteen, the crystal shone crimson.  When the crystal turned to black it was time to report to the Sleepshop. Those who didn't report for annihilation, those who tried to escape, were hunted down by the Seep Sleep men, and exterminated.   Logan was a DS man, efficient, fast and cruel.  But when one day the crystal in Logan's hand began to flicker, black-red-black, Logan discovered he didn't want to die.

A Corgi 1976 paperback in good condition based on the Hancer Standard.   

(Logan's Run, the movie based on the book, starred Michael York, Jenny Agutter, Richard Jordon, Roscoe Lee Browne, Farrah Fawcett-Majors and Peter Ustinov)