oxammite
/ɒkˈsamʌɪt/Mineralogy
noun
Native ammonium oxalate, NH4CO·CONH4, an orthorhombic mineral occurring as colourless to yellowish-white lamellar masses in guano deposits.
Origin
Late 19th century; earliest use found in Charles Shepard (1804–1886). From ox- (in oxalo-) + amm- + -ite.