Brownish Mineral Commonly Used as Iron Ore

This page is the CodyCross answer for the clue below from Mexico, Group 1371, Puzzle 4 (Olmec and Maya).

Question is: Brownish Mineral Commonly Used as Iron Ore

and the answer is: LIMONITE

Word Meaning:

LIMONITE — (mineralogy) Any of several natural hydrous iron oxides; often a mixture of goethite and hematite with clays and manganese oxide.

Definitions from Wiktionary.