The diamond was not very well known among the ancients; and if we add to this reason the similarity between the words smiris, the Egyptian asmir, "emery", a species of corindon used to polish precious stones, and shmyr, the Hebrew word supposed to mean the diamond, we may conclude with probability that the limpid corindon was intended.    From Wordnik.com.  [The Catholic Encyclopedia, Volume 14: Simony-Tournon] Reference