This is a microscopic colony of a green alga called "Botryococcus Braunii”. Colonies are held together by a lipid (oily) biofilm and you can see old droplets around the edge of the colony. Typically around 30–40% of the dry weight of a colony is oil. Blooms of Botryococcus braunii have been shown to be toxic to other micro-organisms and fishes but they may have other applications than being a source of food. Botryococcus braunii has great potential for algaculture because of the hydrocarbons it produces, which can be chemically converted into fuels. Botryococcus oils can be used as feedstock for hydrocracking in an oil refinery to produce octane (gasoline), kerosene, and diesel.