Webster's Revised Unabridged Dictionary · 1913

Pisolite

Pisolite , noun

[Greek {not transcribed} a pea + -lite: compare French pisolithe.]

(Mineralogy) A variety of calcite, or calcium carbonate, consisting of aggregated globular concretions about the size of a pea; -- called also peastone, peagrit.

Oolite is similar in structure, but the concretions are as small as the roe of a fish.