A white variety of olivine that is mostly magnesium silicate Mg2SiO4.(noun)
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Use "forsterite" in a sentence
"It was the crew of Apollo 15 who first found green olivine - specifically, a magnesium-rich variety that goes by the name forsterite, which is also the kind that was spotted by Spitzer."
"The resulting magnesium silicate recrystallizes to form forsterite and silica in the temperature range 800-850° C, as an exothermic process."
"The existence of forsterite in a star like HOPS-68 is not entirely without precedent; the crystals have been found in the vicinity of young stars before, but never so high up - and never behaving like rain before."