Assertion: siderite | /r/HasProperty | removed after calcination
Facets:
value: formerly
type: TEMPORAL
value: to the oxide
type: TRANSITIVE-OBJECT
Source sentences:
text: Formerly the siderite was removed after calcination to the oxide, but since the advent of the separators with intense magnetic fields direct separation of the raw siderite as a magnetic product has superseded the older process.