Assertion: fountain pen's barrel | /r/MadeOf | a variety of materials
Facets:
Source sentences:
text: The first barrels were made of black hard rubber since they were ink-resistant and easily machinable, but barrels today can be made from a variety of materials.
text: The first barrels were made of black hard rubber since they were ink-resistant and easily machinable, but barrels today can be made from a variety of materials.