It typically forms as irregular masses or botryoidal forms. It is a globular, botryoidal or stalactic concretionary form of opal. The typical habit is as earthy botryoidal masses. Botryoidal or reniform cassiterite is called "wood tin". It is green, often botryoidal, and occurs in the oxidation zone of some metal deposits. The most typical form is as botryoidal rounded grape-like masses. Typically the form is vein or fracture filling, nodular, or botryoidal in habit. It is typically found as botryoidal or rounded masses and crusts, or vein fillings. Botryoidal geyserite is known as fiorite. Drusy crusts of tiny intergrown crystals are common, also encrustations and mammillary or botryoidal surfaces. Aggregation of crystals or aggregates (fibrous, botryoidal, radiating, massive). It has a pearly lustre and forms botryoidal masses. These nearby spheres are then fused together to form the botryoidal cluster. "Botryolite" is a botryoidal form of datolite. The term botryoidal refers to the subspherical, grape-like geyserite structures around the vent.