Today we have a special guest post from our archaeobotanist Kathleen Forste. Her post follows.
Hi there! I'm Kathleen, a member of the archaeobotany team, giving a brief report on flotation this season. We are processing the soil samples that each grid produces as they continue to reveal more and more about Ashkelon's occupants.
What is flotation? In essence it is washing away the dirt in soil samples taken from specific archaeological contexts in order to recover carbonized botanical remains -- predominantly burned seeds and wood charcoal -- as well as smaller artifacts that might be overlooked during excavation -- fish bones and other small bones, bits of colored glass, small pieces of ceramic vessels, beads, etc. To process the samples we use a machine called a Flote-Tech, a fantastic piece of moveable equipment that pumps water from a holding tank into a flotation tank through a series of jets that help to wash away the dirt and separate the light fraction (the material that floats, like carbonized plant matter) and heavy fraction (the material that sinks, like ceramics and large bone). I am training a handful of our volunteers to use the Flote-Tech to continue the flotation process for the duration of the season.
So far, we've recovered a lot of fish bone and carbonized plant remains from Grid 51.
We have also recovered some cool colored glass from Grid 16 that is hundreds of years old.
What can all this material tell us? We use the archaeobotanical data to learn about what the inhabitants were consuming and growing in fields and gardens, and what types of wood they were using as construction materials and as fuel for their fires, among other things. The class of smaller bones can tell us more about fishing practices and fish consumption. These two data sets would be underrepresented if the material were recovered in excavation alone, and thus give us a more complete look into the economies and lives of Ashkelon's inhabitants throughout it's history.