I worked on the NASA SETI Program in the 1980s in the Deep Space Network at NASA/JPL in Pasadena, CA. I led a small team of engineer/astronomers who provided a wide variety of planning, scheduling, and execution of radio astronomy and radar astronomy experiments withing the DSN. Sometime during that time, a senior manager of SETI, N. A. Renzetti, arranged for the late Dr. Philip Morrison to meet with my team and a few others one afternoon. There was no particular agenda, but we understood that we were there to hear about Dr. Morrison's opinions about SETI. One of my colleagues asked what his definition of life was. He replied that, boiled down to its essentials, it was the ability to reproduce. He then mentioned, almost in passing, that he had heard from a geologist at MIT about a particular variety of clay that, if given the right raw materials, could reporduce itself, but, if the raw materials were present, but the clay was not, no clay would be produced. I asked the obvious question: "How was the original batch of this clay produced?" Dr. Morrison replied that he really didn't know, but made a joke about chickens and eggs.... I've occasionally wondered about that clay over the years. Has anyone else every heard of this (possibly) prolific stuff?