Olivine grains erupted at the summit of Kīlauea

Backscattered electron image of olivine grains erupted at the summit of Kīlauea. Numbers in grains are forsterite (Fo) contents that measure the ratio of Magnesium (Mg) and Iron (Fe). Fo=100*(Mg/(Mg+Fe)). Panel A shows a typical olivine that has one composition (Fo83). Panel B shows the new olivine population identified in episode 44 that has different composition on the rim, shown by the light grey color and which has lower Mg (Fo81).