• Webster's Revised Unabridged Dictionary
    • n Spherulite (Min) A minute spherical crystalline body having a radiated structure, observed in some vitreous volcanic rocks, as obsidian and pearlstone.
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Century Dictionary and Cyclopedia
    • n spherulite A vitreous globule, such as those of which perlite is made up, having a more or loss perfectly developed concentric and at the same time decidedly radiating fibrous structure. The highly silicious volcanic rocks not unfrequently have a spherulitic structure.
    • n spherulite Same as radiolite, 2.
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Chambers's Twentieth Century Dictionary
    • Spherulite a radiating spherical group of minute acicular crystals common in silicious volcanic rocks
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Webster's Revised Unabridged Dictionary
Cf. F. sphérulite,
Chambers's Twentieth Century Dictionary
Fr.,—L. sphæra—Gr. sphaira.


In literature:

Occasionally they show a fluxional banding; they may also be spherulitic or vesicular.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 2" by Various