What is a variety of opal occuring in the cavities of volcanic tufa, in smooth and shining globular and botryoidal masses, having a pearly luster; -- so called from Fiora, in Ischia called?

fiorite — A variety of opal occuring in the cavities of volcanic tufa, in smooth and shining globular and botryoidal masses, having a pearly luster; -- so called from Fiora, in Ischia. (Webster's 1913.)

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