Excavations at Masada have revealed what type of olives were eaten in Roman times. Ran Shapira, in an article at Haarretz, writes:
"Masada's olives sparked particular interest because an in-depth inquiry into their qualities found that since the Roman era, there has been no significant change in their agriculture. Masada residents ate olives from the exact same varieties that grow in Israel today, namely, Syrian, Nabali and Melisi. Researchers identified the varieties by inspecting the pits, their structure and symmetry. Olive pits were found whole, an indication that the olives were eaten in pickled form, and not used to produce oil. This speculation was reinforced by the fact that 90 percent of the olives on Masada were of the Nabali variety, which is most suited for pickling among the local varieties that grow in Israel.
The remaining 10 percent were primarily Syrian or Melisi olives, but there were also some amounts found of two varieties that do not grow in Israel, and need to be imported from neighboring countries. One is the Shami olive, which grows in Syria, and the other is the Toffahi, from Egypt. The pits of these varieties are substantially different from those of the local varieties. According to Kislev, who lectured this week at Masada at the Dead Sea Conference on Environmental Resources and Society, the two imported varieties are considered luxuries to this day, and Arab villages tend to use them as decoration for weddings and other occasions. He estimates that they were imported to Masada during the time when wealthy and high-ranking people lived there, such as King Herod himself or the Roman generals who besieged the mountain."