Assertion: siderite's use | /r/HasProperty | brown iron ore
Facets:
Source sentences:
text: , The word siderite is used in a number of rarer minerals and except in the fact that , Its main modern use is as an iron ore, being referred to as brown iron ore
text: , The word siderite is used in a number of rarer minerals and except in the fact that , Its main modern use is as an iron ore, being referred to as brown iron ore