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limestone vs. travertine

limestone

[lahym-stohn] / ˈlaɪmˌstoʊn /

noun

a sedimentary rock consisting predominantly of calcium carbonate, varieties of which are formed from the skeletons of marine microorganisms and coral: used as a building stone and in the manufacture of lime.

travertine

[trav-er-teen, -tin] / ˈtræv ərˌtin, -tɪn /

Also travertin

a form of limestone deposited by springs, especially hot springs, used in Italy for building.