Assertion: metamorphic tourmaline | /r/HasProperty | derived by melt
Facets:
value: at the early magmatic stage
type: TEMPORAL
Source sentences:
text: These data together with their morphology and petrography indicate that the Conadong granitic tourmalines were derived by the melts at the early magmatic stage, whereas the pegmatitic tourmalines precipitated from magmatic–hydrothermal fluids at the late magmatic stage.