Assertion: tourmaline's discovery | /r/HasProperty | atomic
Facets:
Source sentences:
text: discovery (1887) atomic mass 72.64 72.59 density (g/cm3) 5.5 5.35 melting point (°C) high 947 color gray gray oxide type refractory dioxide refractory dioxide oxide density (g/cm3) 4.7 4.7 oxide activity feebly basic feebly basic chloride boiling point (°C) under 100 86 (GeCl 4 ) chloride density (g/cm3)