Grains of the translucent mineral olivine, which is rarely found in nature in its pure form, fell on the inhabitants of Hawaii.
The eruption of the Kilauea volcano has generated many unusual phenomena - for example, blue flames bursting from the ground. Now the inhabitants of the island are reporting green crystals falling from the sky.
These crystals are olivines - magnesian-ferruginous silicates. They are so common on the planet that experts estimate that they make up 50 percent of the Earth's upper mantle. During an eruption, magma washes away part of the oceanic crust, which is similar in composition to the mantle, so dark igneous rocks often acquire a green tint. However, pure olivine, which jewelers usually call peridot, is difficult to find. Even more rarely, it falls from the sky.
Usually, olivine comes to the surface along with slowly oozing lava, and therefore remains trapped in the rocks. In this case, the lava erupted so sharply and powerfully that its particles cooled in the air, allowing the olivine to quickly crystallize separately.
Alexey Evglevsky